EG-2 ENGINE - 1NZ-FE ENGINE

1NZ-FE ENGINE
DESCRIPTION
The 1NZ-FE engine is a in-line, 4-cylinder, 1.5 liter, 16-valve DOHC engine.
The VVT-i (Variable Valve Timing-intelligent) system, DIS (Direct Ignition System) and ETCS-i (Electronic
Throttle Control System-intelligent) are used on this engine in order to realize high performance, quietness,
fuel economy and clean emission.

00REG01Y

00REG02Y

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-3

Engine Specifications 
No. of Cyls. & Arrangement 4-Cylinder, In-line
Valve Mechanism 16-Valve DOHC, Chain Drive (with VVT-i)
Combustion Chamber Pentroof Type
Manifolds Cross-Flow
Fuel System SFI
Ignition System DIS
Displacement cm3 (cu. in.) 1497 (91.3)
Bore x Stroke mm (in.) 75.0 x 84.7 (2.95 x 3.33)
Compression Ratio 10.5 : 1
Max. Output*1 (SAE-NET) 79 kW @ 6000 rpm (106 HP @ 6000 rpm)
Max. Torque*1 (SAE-NET) 139 N.m @ 4200 rpm (103 ft lbf @ 4200 rpm)
Open -7  - 33 BTDC
Intake
Valve Close 52 - 12 ABDC
Timingg Open 42 BBDC
Exhaust
Close 2 ATDC
Firing Order 1-3-4-2
Research Octane Number 90 or higher
Octane Rating 87 or higher
Oil Grade ILSAC
Tailpipe Emission Regulation TIRE2, ULEV-II
Evaporative Emission Regulation ORVR
Mass*2
Engine Service Mass M/T 83.2 (183.4)
kg (lb)
(Reference) A/T 77.8 (171.5)
*1: Maximum output and torque rating is determined by revised SAE J1349 standard.
*2: Weight shows the figure with the oil fully filled.

Valve Timing 
: IN Opening Angle
: EX Opening Angle
VVT-i Operation Angle TDC
2
7

33

52
42

VVT-i Operation Angle 12

BDC 247EG02

Downloaded from www.Manualslib.com manuals search engine

 EG-4 ENGINE - 1NZ-FE ENGINE

FEATURES OF 1NZ-FE ENGINE

The 1NZ-FE engine has been able to achieve the following performance through the adoption of the items
listed below.
(1) High performance and fuel economy
(2) Low noise and vibration
(3) Lightweight and compact design
(4) Good serviceability
(5) Clean emission

Section Item (1) (2) (3) (4) (5)

A cylinder block made of aluminum is used. 
An offset crankshaft is used.   
Engine Proper
The taper squish shape is used for the combustion
 
chamber.
Valve A timing chain and chain tensioner are used.   
Mechanism The VVT-i system is used.  
Intake manifold made of plastic is used. 
The linkless-type throttle body is used.  
Intake and A stainless steel exhaust manifold is used. 
Exhaust System Two TWCs (Three Way Catalytic Converter) are used. 
A rearward exhaust layout is used to realize the early

activation of the catalyst.
12-hole type injector is used.  
The fuel returnless system is used.   
Fuel System
Quick connectors are used to connect the fuel hose with

the fuel pipes.
The long-reach type spark plugs are used. 
Ignition System The DIS (Direct Ignition system) makes ignition timing
  
adjustment unnecessary.
The ETCS-i (Electronic Throttle Control
 
System-intelligent) is used.
The non-contact sensor is used in the throttle position

Engine Control sensor and accelerator pedal position sensor.
System
y The cranking hold function is used. 
Evaporative emission control system is used. 
The use of an air fuel ratio sensor allows for precise

control.

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-5

ENGINE PROPER

1. Cylinder Head

The injectors are installed in the cylinder head to reduce the distance from injector to intake valve, thus
it prevents the fuel from adhering to the intake port walls, and reduce exhaust emissions.

The routing of the water jacket in the cylinder head is optimized to achieve high cooling performance.

Through the use of the taper squish combustion chamber, the engines knocking resistance and fuel
efficiency have been improved.

Injector
IN

EX

Water Jacket

Taper Squish 247EG03

2. Cylinder Block

Lightweight aluminum alloy is used for the cylinder block.

Through the use of the offset crankshaft, the bore center is shifted 12 mm (0.472 in.) towards the intake,
in relation to the crankshaft center. Thus, the side force to cylinder wall is reduced when the maximum
pressure is applied, which contributes to fuel economy.

Bore Center
Maximum
Pressure

Crankshaft
Center

Crankshaft Center Offset Crankshaft Center Crankshaft

247EG04 193EG05

Downloaded from www.Manualslib.com manuals search engine

 EG-6 ENGINE - 1NZ-FE ENGINE

The liners are the spiny-type, which have been manufactured so that their casting exterior forms a large
irregular surface in order to enhance the adhesion between the liners and the aluminum cylinder block.
The enhanced adhesion helps improve heat dissipation, resulting in a lower overall temperature and heat
deformation of the cylinder bores.
Irregularly shaped outer
casting surface of liner Cylinder Block
A

Liner

A - A Cross Section

00REG19Y

3. Piston

The piston is made of aluminum alloy

The piston head portion is used a taper squish shape to accomplish fuel combustion efficiency.

Semi floating type piston pins are used.

By increasing the machining precision of the cylinder bore diameter, only one size of piston is available.

Taper Squish Shape

Piston Ring

247EG06

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-7

4. Connecting Rod

The connecting rods and caps are made of high
strength steel for weight reduction.

Nutless-type plastic region tightening bolts are
used for a light design.

Plastic Region Tightening Bolts

171EG07

5. Crankshaft

The diameter and width of the pins and journals have been reduced, and the pins for the No.1 and No.4
cylinders have been made highly rigid to realize a lightweight and low-friction performance.

The crankshaft has 5 journals and 4 balance weights.

A crankshaft position sensor rotor is pressed into the crankshaft to realize an integrated configuration.

Crank Pin
Oil Hole

Crankshaft Position No.5 Journal

Sensor Rotor

No.1 Journal No.4 Journal

Balance Weight
No.2 Journal No.3 Journal
171EG08

Downloaded from www.Manualslib.com manuals search engine

 EG-8 ENGINE - 1NZ-FE ENGINE

VALVE MECHANISM

1. General
 The shimless type valve lifter is used to increase the amount of the valve lift.
 The intake and exhaust camshafts are driven by a timing chain.
 The VVT-i system is used to realize fuel economy, engine performance and reduce exhaust emissions. For
details of VVT-i control, see page EG-41.

Timing Chain Exhaust Camshaft

VVT-i
Controller
Camshaft

Intake
Camshaft Valve Lifter
Chain
Tensioner

Valve

Chain
Tension Arm
Chain Guide
171EG09 165EG12

Service Tip
The adjustment of the valve clearance is accomplished by selecting and replacing the appropriate
valve lifters. Adjusting valve lifters are available in 35 increments of 0.020 mm (0.0008 in.), from
5.060 mm (0.1992 in.), to 5.740 mm (0.2260 in.).
For details, refer to 2006 Yaris Repair Manual (Pub. No. RM00R0U).

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-9

2. Camshaft
 Oil passages are provided in the intake camshaft in order to supply engine oil to the VVT-i system.
 A VVT-i controller is provided on the front of the intake camshaft to vary the timing of the intake valves.
 A Timing rotor is provided behind the intake camshaft to trigger the camshaft position sensor.

Exhaust Camshaft

Timing Rotor

VVT-i Controller Intake Camshaft

Oil Passage (Advance)

Oil Passage (Retard)

247EG08

3. Timing Chain and Chain Tensioner

 A roller type timing chain with an 8.0 mm (0.315 in.) pitch is used to make the engine compact and reduce
noise.
 The timing chain is lubricated by an oil jet.
 The chain tensioner uses a spring and oil pressure to maintain proper chain tensioner at all times. The chain
tensioner suppresses noise generated by the timing chain.
 A ratchet type non-return mechanism is used in the chain tensioner.

Chain Tensioner 

Timing Chain
Spring
Plunger

Chain Damper

Cam
Chain
Slipper
Check Ball Oil Jet
Cam Spring

247EG09

Downloaded from www.Manualslib.com manuals search engine

 EG-10 ENGINE - 1NZ-FE ENGINE

4. Timing Chain Cover

 A single-piece, aluminum diecast timing chain cover that entirely seals the front portion of the cylinder
block and cylinder head is used.
 A service hole for the chain tensioner is provided in the timing chain cover to improve serviceability.

Service Hole for

Chain Tensioner

Oil Pump
171EG31 171EG32

Front View Back View

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-11

LUBRICATION SYSTEM
1. General
 The lubrication circuit is fully pressurized and oil passes through an oil filter.
 A trochoid gear type oil pump, which is driven directly by the crankshaft, is provided in the front of the
cylinder block.
 The oil filter is installed diagonally downward from the side of the cylinder block to realize excellent
serviceability.
 The intake camshaft is provided with a VVT-i controller, and cylinder head is provided with a camshaft
timing oil control valve. This system is operated by the engine oil.

Camshaft Timing
Oil Control Valve

VVT-i
Controller

Oil Capacity  Liter (US qts, Imp qts)

Chain Dry 4.1 (4.3, 3.6)
Tensioner with Oil Filter 3.7 (3.9, 3.3)
Oil Filter without Oil Filter 3.4 (3.6, 3.0)

Oil Pump Oil Strainer

171EG14

Oil Circuit 

Main Oil Hole

Cylinder Head
Crankshaft Oil Jet
Journal Camshaft Timing
Oil Filter Oil Control Valve
Filter
Relief Connecting
Valve Rod Chain Intake Exhaust
Tensioner Camshaft Camshaft
Oil Pump Journal Journal
Oil Jet
Timing Chain Camshaft Timing
Oil Strainer Oil Control Valve
Piston
VVT-i

Oil Pan
171EG15

Downloaded from www.Manualslib.com manuals search engine

 EG-12 ENGINE - 1NZ-FE ENGINE

COOLING SYSTEM
 The cooling system is a pressurized, forced-circulation type.
 A thermostat with a bypass valve is located on the water inlet housing to maintain suitable temperature
distribution in the cooling system.
 An aluminum radiator core is used for weight reduction.
 The flow of the engine coolant makes a U-turn in the cylinder block to ensure a smooth flow of the engine
coolant.
 A single cooling fan provides both the cooling and air conditioner performance.
 The TOYOTA genuine Super Long Life Coolant (SLLC) is used.

From Heater Core

Water Pump To Radiator

To Heater Core
To Throttle Body

From Radiator

00REG16Y

System Diagram 

Bypass Heater Core

Passage Cylinder Head

Cylinder Block

Water Pump

Throttle
Thermostat Body
Radiator
193EG08

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-13

Engine Coolant Specifications 

TOYOTA genuine Super Long Life

Coolant (SLLC) or similar high quality
ethylene glycol based non-silicate,
non-amine, non-nitrite and non-borate
Type coolant with long-life hybrid organic acid
technology (coolant with long-life hybrid
organic acid technology is a combination
Engine of low phosphates and organic acids.) Do
Coolant not use plain water alone.
Color Pink
Capacity M/T 4.8 (5.1, 4.2)
Liters (US qts, Imp. qts) A/T 4.7 (5.0, 4.1)
First Time 100,000 miles (160,000 km)
Maintenance Intervals
Subsequent Every 50,000 miles (80,000 km)
Thermostat Opening Temperature C (F) 80 - 84 (176 - 183)

 SLLC is pre-mixed (the U.S.A. models: 50 % coolant and 50 % deionized water, the Canada. models:
55 % coolant and 45 % deionized water). Therefore, no dilution is needed when SLLC in the vehicle is
added or replaced.
 If LLC is mixed with SLLC, the interval for LLC (ever 40,000 km/24,000 miles or 24 months) should
be used.

Downloaded from www.Manualslib.com manuals search engine

 EG-14 ENGINE - 1NZ-FE ENGINE

INTAKE AND EXHAUST SYSTEM

1. General

A plastic intake manifold is used for weight reduction.

The linkless-type throttle body is used to realize excellent throttle control.

ETCS-i (Electronic Throttle Control System-intelligent) provides excellent throttle control. For details,
see page EG-36.

The exhaust pipe uses a ball joint in order to achieve a simple construction and reliability.

Exhaust Manifold

Main
Muffler

Sub Muffler

TWCs

Intake Manifold
00REG06Y

Air Cleaner

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-15

2. Air Cleaner

A nonwoven, full-fabric type air cleaner element is used.

A charcoal filter, which adsorbs the HC that accumulates in the intake system when the engine is stopped,
is used in the air cleaner cap in order to reduce evaporative emissions.

Air Cleaner Cap

Charcoal Filter
Air Cleaner Element
(Nonwovens Fabric)

00REG03Y

Service Tip
The charcoal filter, which is maintenance-free, cannot be removed from the air cleaner cap.

3. Throttle Body

The linkless-type throttle body is used and it realizes excellent throttle control.

A DC motor with excellent response and minimal power consumption is used for the throttle control motor.
The ECM performs the duty ratio control of the direction and the amperage of the current that flows to
the throttle control motor in order to regulate the opening angle of the throttle valve.

DC Motor

Throttle Valve

Throttle Position Sensor

Reduction Gears 00REG04Y

Downloaded from www.Manualslib.com manuals search engine

 EG-16 ENGINE - 1NZ-FE ENGINE

4. Intake Manifold

The intake manifold has been made of plastic to
reduce the weight and the amount of heat
transferred from the cylinder head. As a result,
it has become possible to reduce the intake Mesh Type Gasket
temperature and improve the intake volumetric
efficiency.

A mesh type gasket is used in order to reduce
the intake noise.

00REG07Y

5. Exhaust Pipe and Muffler

A ball joint is used to joint the exhaust manifold to the exhaust front pipe, and the exhaust front pipe to the
exhaust tail pipe. As a result, a simple construction and improved reliability have been realized.

Main Muffler
Ball Joint

Tail Pipe
Gasket
Front Pipe
Ball Joint
TWCs

Sub Muffler
Ball Joint
00REG08Y

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-17

FUEL SYSTEM

1. General

The fuel returnless system is used to reduce evaporative emissions.

A fuel tank made of multi-layer plastic is used.

A fuel cut control is used to stop the fuel pump when the SRS airbag is deployed in a front or side collision.
For details, see page EG-45.

A quick connector is used to connect the fuel pipe with the fuel hose to realize excellent serviceability.

A compact 12-hole type injector is used to ensure the atomization of fuel.

The ORVR (On-Board Refueling Vapor Recovery) system is used. For details, see page EG-46.

Fuel Pump

Fuel filter

Pressure Regulator Canister

Fuel Sender Gauge

Fuel Cutoff Valve

Fuel Tank

Quick Connector

Injector

View from Bottom

00REG12Y

Downloaded from www.Manualslib.com manuals search engine

 EG-18 ENGINE - 1NZ-FE ENGINE

2. Fuel Returnless System

This system is used to reduce the evaporative emission. As shown below, integrating the fuel filter, pressure
regulator, fuel sender gauge, and fuel cutoff valve with module fuel pump assembly enables to discontinue
the return of fuel from the engine area and prevent temperature rise inside the fuel tank.
Injector

Pulsation
Damper Delivery Pipe

Pressure Regulator
To Canister
Fuel Cutoff Valve Fuel Tank

Module
Fuel Filter Fuel Pump
Assembly
Fuel Pump
179EG11

3. Fuel Tank
Low permeability has been realized through the use of the multi-layered plastic fuel tank. This fuel tank
consists of six layers using four types of materials.

HDPE (High Density Polyethylene)

Regrind Material
Fuel Tank Outside
Adhesive
EVOH (Ethylene Vinyl Alcohol Copolymer)
Fuel Tank Inside Adhesive
HDPE (High Density Polyethylene)
00REG13Y

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-19

IGNITION SYSTEM

1. General
 A DIS (Direct Ignition System) is used. The DIS in this engine is an independent ignition system, which
has one ignition coil for each cylinder. The DIS ensures the ignition timing accuracy, reduces high-voltage
loss, and realizes the overall reliability of the ignition system by eliminating the distributor.
 The spark plug caps, which connect to the spark plugs, are integrated with the ignition coils. Also, the
igniters are enclosed to simplify the system.
 Long-reach type iridium-tipped spark plugs are used.

Ignition Coil
ECM
(with Igniter)
Crankshaft
Position +B
Sensor IGT1 No.1
Cylinder

Camshaft IGT2 No.2

Position Cylinder
Sensor
IGT3 No.3
Cylinder

Various
Sensor IGT4 No.4
Cylinder
IGF

165EG25

Ignition Coil with Igniter 

Igniter

Iron Core
Primary Coil

Secondary Coil
Plug Cap
171EG27

Downloaded from www.Manualslib.com manuals search engine

 EG-20 ENGINE - 1NZ-FE ENGINE

2. Spark Plug
 Long-reach type iridium-tipped spark plugs are used.
 Long-reach type of spark plugs allows the area of the cylinder head to receive the spark plugs to be made
thick. Thus, the water jacket can be extended near the combustion chamber, which contributes to cooling
performance.
 Iridium-tipped spark plugs are used to realize a 100,000 km (62,500 mile) maintenance-free operation.
By making the center electrode of iridium, the same ignition performance as the platinum-tipped type
spark plug and excellent of durability have been realized.

Iridium Tip
Long-Reach Type Conventional Type

281EG73

Specification 

DENSO SK16R11
NGK IFR5A-11
Plug Gap mm (in.) 1.1 (0.043)

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-21

CHARGING SYSTEM
 A compact and lightweight segment conductor type generator that generates high amperage output in a
highly efficient manner is used as standard equipment.
 This generator has a joined segment conductor system, in which multiple segment conductors are welded
together to form the stator. Compared to the conventional wiring system, the electrical resistance is
reduced due to the shape of the segment conductors, and their arrangement helps to make the generator
compact.

Stator Segment Stator Stator Stator Conductor Wire

Conductor Segment
Conductor Conductor Wire

A B
Joined B - B Cross
A - A Cross
Section Section
Joined Segment
A B Wiring System
Conductor System
206EG40 206EG41

Segment Conductor Conventional Type Generator

Type Generator

Stator
Segment
Conductor

Cross Section

206EG42

Stator of Segment Conductor

Type Generator

Specifications 

Type SE08
Rated Voltage 12 V
Rated Output 80 A
Initial Output Starting Speed 1,250 rpm Max.

Downloaded from www.Manualslib.com manuals search engine

 EG-22 ENGINE - 1NZ-FE ENGINE

Wiring Diagram 
Generator
B

M
IG
Ignition Switch
S

Regulator

L Discharge
Warning Light

00REG20Y

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-23

STARTING SYSTEM

1. General
 A P (conventional planetary reduction) type starter is used in the models for U.S.A.
 A PS (planetary reduction-segment conductor motor) type starter is used in the models for Canada and
cold areas of the U.S.A.

Surface Commutator
Permanent Magnet

Armature

Brush

PS Type
(PS1.6)

Length

P Type
(P0.8)

271EG38

Specification 

Canada,
Destination U.S.A.
Cold Areas of U.S.A.
Starter Type P Type PS Type
Rating Output 0.8 kW 1.6 kW
Rating Voltage 12 V

Length*1 mm (in.) 154 (6.1) 133 (5.2)
Weight g (lb) 2800 (6.2)

Rotation Direction*2 Clockwise

*1: Length from the mounted area to the rear end of the starter
*2: Viewed from Pinion Side

Downloaded from www.Manualslib.com manuals search engine

 EG-24 ENGINE - 1NZ-FE ENGINE

2. PS (Planetary reduction-Segment conductor motor) Type Starter

Construction
 Instead of constructing the armature coil with P type of round-shaped conductor wires, the PS type starter
uses square conductors. With this type of construction, the same conditions that are realized by winding
numerous round-shaped conductor wires can be achieved without increasing the mass. As a result, the
output torque has been increased, and the armature coil has been made compact.
 Because the surface of the square-shaped conductors that are used in the armature coil functions as a
commutator, the overall length of the PS type starter has been shortened.

Conventional Type
Brush
Armature Square-Shaped Round-Shaped
Conductor Conductor
B Commutator

A
Brush A - A Cross Section B - B Cross Section
Armature A (PS Type) (P Type)
Surface Commutator

PS Type
206EG20

 Instead of the field coils used in the P type starter, the PS type starter uses two types of permanent
magnets: the main magnets and the interpolar magnets. The main and interpolar magnets are arranged
alternately inside the yoke, allowing the magnetic flux that is generated between the main and interpolar
magnets to be added to the magnetic flux that is generated by the main magnets. In addition to increasing
the amount of magnetic flux, this construction shortens the overall length of the yoke.

Main Magnet Magnetic Flux Generated by

Interpolar Magnet Relationship Between Main Magnets
Yoke Main Magnet Magnetic Flux Generated by
Interpolar Magnets

S N
N S
S N

Armature

Cross Section of Yoke

222EG15

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-25

ENGINE CONTROL SYSTEM

1. General
The engine control system for the 1NZ-FE engine has the following systems.

06 05
System Outline
Model Model
SFI
An L-type EFI system detects the intake air mass with a
Electronic Fuel  
hot-wire type air flow meter.
Injection
ESA Ignition timing is determined by the ECM based on signals
Electronic Spark from various sensors. The ECM corrects ignition timing in  
Advance response to engine knocking.
Optimally controls the throttle valve opening in accordance
with the amount of accelerator pedal effort and the condition  -
ETCS-i of the engine and vehicle.
Electronic
Throttle Control
A linkless-type is used without an accelerator.
System-intelligent
An accelerator pedal position sensor is provided on the
accelerator pedal.  -
See page EG-36

A non-contact type throttle position sensor and accelerator
pedal position sensor are used.
VVT-i
Variable Valve Controls the intake camshaft to optimal valve timing in
 
Timing-intelligent accordance with the engine condition.
See page EG-41

Fuel pump operation is controlled by signals from the ECM.
Fuel Pump Control

The operation of the fuel pump will stop when the airbag  
See page EG-45
is deployed.
Air Fuel Ratio Sensor Maintains the temperature of the air fuel ratio sensor or
and Oxygen Sensor oxygen sensor at an appropriate level to realize accuracy of  -
Heater Control detection of the oxygen concentration in the exhaust gas.
Maintains the temperature of the oxygen sensor at an
Oxygen Sensor
appropriate level to realize accuracy of detection of the - 
Heater Control
oxygen concentration in the exhaust gas.
The ECM controls the purge flow of evaporative emissions
 
(HC) in the canister in accordance with engine conditions.
Using 3 VSVs and a vapor pressure sensor, the ECM detects any
Evaporative evaporative emission leakage occurring between the fuel tank - 
Emission and charcoal canister through changes in the fuel tank pressure.
Control Approximately five hours after the ignition switch has been
See page EG-46 turned OFF, the ECM operates the canister pump module to
detect any evaporative emission leakage occurring in the  -
evaporative emission control system through changes in the
reference orifice pressure.
Air Conditioner By turning the air conditioner compressor OFF in accordance
 
Cut-off Control*1 with the engine condition, drivadility is maintained.
Cooling Fan Control Cooling fan operation is controlled by signals from ECM based
 
See page EG-56 on the engine coolant temperature sensor signal (THW).
*1: for Models with Air Conditioning System

Downloaded from www.Manualslib.com manuals search engine

 EG-26 ENGINE - 1NZ-FE ENGINE

06 05
System Outline
Model Model
Starter Control
Once the ignition switch is turned to the START position,
Cranking Hold this control continues to operate the starter until the engine  -
Function
is started.
See Page EG-57
Prohibits fuel delivery and ignition if an attempt is made to
Engine Immobilizer*2  
start the engine with an invalid ignition key.
Diagnosis When the ECM detects a malfunction, the ECM diagnoses
 
See Page EG-59 and memorizes the failed section.
Fail-Safe When the ECM detects a malfunction, the ECM stops or
 
See Page EG-59 controls the engine according to the data already in memory.
*2: for Models with Engine Immobilizer System

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-27

2. Construction
The configuration of the engine control system in the 1NZ-FE engine is shown in the following chart.

SENSORS ACTUATORS
VG
MASS AIR FLOW METER SFI
#10
THA No.1 INJECTOR
INTAKE AIR TEMPERATURE #20
SENSOR No.2 INJECTOR
#30
No.3 INJECTOR
CRANKSHAFT POSITION NE #40
No.4 INJECTOR
SENSOR

CAMSHAFT POSITION G2 IGT1 ESA

SENSOR
IGT4
IGNITION COIL
with IGNITER
THROTTLE POSITION VTA1 IGF
SENSOR VTA2 SPARK PLUGS

ENGINE COOLANT THW

TEMPERATURE SENSOR VVT-i

OC1 CAMSHAFT TIMING

ACCELERATOR PEDAL VPA OIL CONTROL VALVE
POSITION SENSOR VPA2
ECM
KNK1
KNOCK SENSOR ETCS- i

M THROTTLE CONTROL
IGNITION SWITCH MOTOR
IGSW

Ignition Signal STSW,

Start Signal STA
FUEL PUMP CONTROL
PARK/NEUTRAL POSITION P,N,D
SWITCH*1 R,L,2 FC CIRCUIT OPENING
RELAY

Shift Lever Position Signal

COMBNATION METER A/F SENSOR & OXYGEN

SPD SENSOR HEATER CONTROL

Vehicle Speed Signal
A/F SENSOR HEATER
HT1A
AIR FUEL RATIO SENSOR A1A+ Bank 1, Sensor 1
(Bank 1, Sensor 1) OXYGEN SENSOR HEATER
HT1B
Bank 1, Sensor 2
HEATED OXYGEN SENSOR OX1B
(Bank 1, Sensor 2)
00REG10Y

(Continued)
*1: for Automatic Transaxle Models

Downloaded from www.Manualslib.com manuals search engine

 EG-28 ENGINE - 1NZ-FE ENGINE

CANISTER PUMP MODULE EVAPORATIVE EMISSION

CONTROL
PPMP
CANISTER PRESSURE SENSOR
CANISTER PUMP MODULE
MPMP
ELS1 LEAK DETECTION PUMP
TAILLIGHT SWITCH
VPMP
ELS3 VENT VALVE
DEFOGGER SWITCH
PRG
STP PURGE VSV
STOP LIGHT SWITCH

ALT
GENERATOR
STATER CONTROL
3 STAR
SHIFT LOCK ECU
STARTER RELAY
ECM
IMI ACCR
ACC CUT RELAY
TRANSPONDER KEY ECU*2
IMO
TC
DLC3 COOLING FAN CONTROL
FAN L
COOLING FAN RELAY No.1

AIRBAG SENSOR ASSEMBLY FAN H

COOLING FAN RELAY No.2

A/C ECU*3 MREL

EFI MAIN RELAY
+B

SKID CONTROL ECU*4 COMBNATION METER

CANH,
CANL W
BATT MIL
BATTERY

00REG11Y
*2: for Models with Engine Immobilizer System
*3: for Models with Air Conditioning System
*4: for ABS Models

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-29

3. Engine Control System Diagram

Park/Neutral
Position Switch*
MIL Ignition
Accelerator Pedal DLC3
Position Sensor Switch
Generator

Circuit Opening Relay ECM

Battery

Throttle
Position
Sensor
Mass Air Flow Meter

Intake Air Temperature
Throttle
Control
Sensor
Motor
Camshaft
Purge VSV Position
Sensor
Ignition Coil
with Igniter

Injector

Engine
Coolant
Temperature
Knock Sensor Sensor

Crankshaft
Canister Position Sensor
Filter TWCs
Fuel Pump

Canister Pump Module

Vent Valve

Leak Detection Pump Heated Oxygen Sensor

Canister Pressure Sensor (Bank 1, Sensor 2)
Air Fuel Ratio Sensor
(Bank 1, Sensor 1)
*: for Automatic Transaxle Models.
00REG14Y

Downloaded from www.Manualslib.com manuals search engine

 EG-30 ENGINE - 1NZ-FE ENGINE

4. Layout of Main Components

Canister Pump Module

Vent Valve

Leak Detection Pump

Canister Pressure Sensor

Heated Oxygen Sensor

(Bank 1, Sensor 2)

ECM

Fuel Pump
VSV (for EVAP) DLC3
Accelerator Pedal
Position Sensor
Mass Air Flow Meter
(Built-in Intake Air Temperature Sensor) Ignition Coil
with Igniter
Camshaft Timing Oil
Control Valve
Camshaft Position
Sensor

Injector Engine Coolant

Temperature
Sensor

Knock Sensor

Crankshaft Position Air Fuel Ratio Sensor

Sensor (Bank 1, Sensor 1)

Throttle Body
00REG15Y

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-31

5. Main components of Engine Control System

General
The main components of the 1NZ-FE engine control system are as follows:

Components Outline Quantity Function

The ECM optimally controls the SFI, ESA, and IAC
ECM 32-bit CPU 1 to suit the operating conditions of the engine in
accordance with the signals provided by the sensors.
As with the heated oxygen sensor, this sensor detects
Air Fuel Ratio
Planar Type the oxygen concentration in the exhaust emission.
Sensor 1
with Heater However, it detects the oxygen concentration in the
(Bank 1, Sensor 1)
exhaust emission linearly.
Heated Oxygen This sensor detects the oxygen concentration in the
Cup Type
Sensor 1 exhaust emission by measuring the electromotive
with Heater
(Bank 1, Sensor 2) force which is generated in the sensor itself.
Mass Air This sensor has a built-in hot-wire to directly detect
Hot-wire Type 1
Flow Meter the intake air mass.
Crankshaft Pickup Coil
This sensor detects the engine speed and performs
Position Sensor Type 1
the cylinder identification.
(Rotor Teeth) (36-2)
Camshaft Pickup Coil
Position Sensor Type 1 This sensor performs the cylinder identification.
(Rotor Teeth) (3)
Engine Coolant
Thermistor This sensor detects the engine coolant temperature
Temperature 1
Type by means of an internal thermistor.
Sensor
Intake Air
Thermistor This sensor detects the intake air temperature by
Temperature 1
Type means of an internal thermistor.
Sensor
This sensor detects an occurrence of the engine
Non-resonant knocking indirectly from the vibration of the
Knock Sensor 1
Flat Type cylinder block caused by the occurrence of engine
knocking.
Throttle Position Non-contact
1 This sensor detects the throttle valve opening angle.
Sensor Type
Accelerator Pedal Non-contact This sensor detects the amount of pedal effort
1
Position Sensor Type applied to the accelerator pedal.
The injector is an electromagnetically-operated
Injector 12-Hole Type 4 nozzle which injects fuel in accordance with signals
from the ECM.

ECM
The 32-bit CPU of the ECM is used to realize the high speed for processing the signals.

Downloaded from www.Manualslib.com manuals search engine

 EG-32 ENGINE - 1NZ-FE ENGINE

Air Fuel Ratio Sensor and Heated Oxygen Sensor

1) General
 The air fuel ratio sensor and heated oxygen sensor differ in output characteristics.
 Approximately 0.4V is constantly applied to the air fuel ratio sensor, which outputs an amperage that
varies in accordance with the oxygen concentration in the exhaust emission. The ECM converts the
changes in the output amperage into voltage in order to linearly detect the present air-fuel ratio.
 The output voltage of the heated oxygen sensor changes in accordance with the oxygen concentration
in the exhaust emission. The ECM uses this output voltage to determine whether the present air-fuel
ratio is richer or leaner than the stoichiometric air-fuel ratio.

A1A+ OX1B
(3.3V)
Air Fuel Heated
Ratio Oxygen
Sensor ECM Sensor ECM
A1A- EX1B
(2.9V)

00REG21Y

Air Fuel Ratio Sensor Circuit Heated Oxygen Sensor Circuit

: Air Fuel Ratio Sensor

: Heated Oxygen Sensor

4.2 1

Air Fuel Ratio Heated Oxygen

Sensor Output (V)* Sensor Output (V)

2.2 0.1

11 (Rich) 14.7 19 (Lean)

Air Fuel Ratio

D13N11

*: This calculation value is used internally in the ECM, and is not an ECM terminal voltage.

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-33

2) Construction
 The basic construction of the air fuel ratio sensor and heated oxygen sensor is the same. However, they
are divided into the cup type and the planar type, according to the different types of heater construction
that are used.
 The cup type sensor contains a sensor element that surrounds a heater.
 The planer type sensor uses alumina, which excels in heat conductivity and insulation, to integrate a
sensor element with a heater, thus realizing the excellent warm-up performance of the sensor.

Alumina
Heater
Dilation Layer Atmosphere Platinum Atmosphere
Electrode
Alumina

Heater

Platinum Sensor Element

Electrode (Zirconia)
Sensor Element (Zirconia)
271EG45

Planer Type Air Fuel Ratio Sensor Cup Type Heated Oxygen Sensor

Warm-up Specification 

Sensor Type Planer Cup Type

Warm-up Time Approx. 10 sec. Approx. 30 sec.

Mass Air Flow Meter

 The compact and lightweight mass air flow meter, which is a plug-in type, allows a portion of the intake
air to flow through the detection area. By directly measuring the mass and the flow rate of the intake air,
the detection precision is ensured and the intake air resistance is reduced.
 This mass air flow meter has a built-in intake air temperature sensor.

Temperature Sensing
Element

Air Flow Intake Air

Temperature Sensor
Platinum Hot-wire
Element 204EG54

Downloaded from www.Manualslib.com manuals search engine

 EG-34 ENGINE - 1NZ-FE ENGINE

Throttle Position Sensor

The throttle position sensor is mounted on the throttle body to detect the opening angle of the throttle valve.
The throttle position sensor converts the magnetic flux density that changes when the magnetic yoke
(located on the same axis as the throttle shaft) rotates around the Hall IC into electric signals to operate the
throttle control motor.

Throttle Body

Throttle Position Magnetic

Sensor Portion Yoke

Hall IC

Cross Section 00REG09Y

Throttle Position
Sensor
V
Magnetic Yoke 5
VTA2
VTA1 Output
Voltage
Hall E VTA1
IC

Hall VC ECM
IC 0 90
VTA2
Throttle Throttle
Valve Valve
Fully Close Fully Open
Throttle Valve Opening Angle

230LX12 238EG79

Service Tip
The inspection method differs from the conventional contact type throttle position sensor because
this non-contact type sensor uses a Hall IC.
For details, refer to the 2006 Yaris Repair Manual (Pub. No. RM00R0U).

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-35

Accelerator Pedal Position Sensor

The non-contact type accelerator pedal position sensor used a Hall IC.
 The magnetic yoke that is mounted at the accelerator pedal arm rotates around the Hall IC in accordance with
the amount of effort that is applied to the accelerator pedal. The Hall IC converts the changes in the magnetic
flux that occur at that time into electrical signals, and outputs them as of accelerator pedal effort to the ECM.
 The Hall IC contains circuits for the main and sub signals. It converts the accelerator pedal depressing
angles into electric signals with two differing characteristics and outputs them to the ECM.
Internal Construction

A
Accelerator
Pedal Arm

Hall IC
Magnetic Yoke

A - A Cross Section 00SEG39Y

Accelerator Pedal
Position Sensor
Magnetic Yoke V
5
VPA
EPA
Output VPA2
Hall VCPA Voltage
IC VPA
VPA2 ECM
Hall
IC 0
EPA2 90
VCP2 Fully Fully
Close Open
Accelerator Pedal Depressed Angle

228TU24 228TU25

Service Tip
The inspection method differs from the conventional contact type accelerator pedal position sensor
because this non-contact type sensor uses a Hall IC.
For details, refer to the 2006 Yaris Repair Manual (Pub. No. RM00R0U).

Downloaded from www.Manualslib.com manuals search engine

 EG-36 ENGINE - 1NZ-FE ENGINE

6. ETCS-i (Electronic Throttle Control System-i)

General
 The ETCS-i is used, providing excellent throttle control in all the operating ranges.
 The accelerator cable has been discontinued, and an accelerator pedal position sensor has been provided
on the accelerator pedal.
 In the conventional throttle body, the throttle valve opening is determined invariably by the amount of
the accelerator pedal effort. In contrast, the ETCS-i uses the ECM to calculate the optimal throttle valve
opening that is appropriate for the respective driving condition and uses a throttle control motor to control
the opening.
 The ETCS-i controls the IAC (Idle Air Control) system and cruise control system.
 In case of an abnormal condition, this system switches to the limp mode.

System Diagram 

Throttle Valve
Throttle Position Sensor

Accelerator Pedal
Position Sensor Throttle
Control
Motor

Mass Air
Skid
Flow Meter ECM Control
ECU*

Ignition Fuel
Coil Injector

: CAN
00REG17Y
*: for ABS Models

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-37

Construction

Throttle Body

Throttle Position
Sensor Portion
Reduction
Gears

Throttle Control View from A

Motor

Magnetic Yoke

Hall IC
(for Throttle Position Sensor)

Throttle Valve

Throttle Control Motor

Cross Section 00REG05Y

1) Throttle Position Sensor

The throttle position sensor is mounted on the throttle body to detect the opening angle of the throttle
valve. For details, refer to Main Components of Engine Control System section on page EG-34.

2) Throttle Control Motor

A DC motor with excellent response and minimal power consumption is used for the throttle control
motor. The ECM performs the duty ratio control of the direction and the amperage of the current that
flows to the throttle control motor in order to regulate the opening of the throttle valve.

Operation

1) General
The ECM drives the throttle control motor by determining the target throttle valve opening in accordance
with the respective operating condition.
 Non-Linear Control
 Idle Air Control

Downloaded from www.Manualslib.com manuals search engine

 EG-38 ENGINE - 1NZ-FE ENGINE

2) Non-Linear Control
It controls the throttle to an optimal throttle valve opening that is appropriate for the driving condition
such as the amount of the accelerator pedal effort and the engine speed in order to realize excellent throttle
control and comfort in all operating ranges.

Control Examples During Acceleration and Deceleration 

: with Control
: without Control


Vehicles
Longitudinal G
0


Throttle Valve
Opening Angle
0

Accelerator Pedal
Depressed Angle
0
Time

005EG13Y

3) Idle Air Control

The ECM controls the throttle valve in order to constantly maintain an ideal idle speed.

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-39

Fail-Safe of Accelerator Pedal Position Sensor

 The accelerator pedal position sensor is comprised of two (main, sub) sensor circuits. If a malfunction
occurs in either one of the sensor circuits, the ECM detects the abnormal signal voltage difference
between these two sensor circuits and switches to the limp mode. In the limp mode, the remaining circuit
is used to calculate the accelerator pedal depressed angle, in order to operate the vehicle under limp mode
control.

ECM

Accelerator Pedal
Position Sensor Open

Main
Sub Main
Sub
Throttle
Throttle Throttle Return Control
Position Valve Spring Motor
Sensor

Accelerator Pedal Throttle Body 199EG45

 If both circuits have malfunctions, the ECM detects the abnormal signal voltage from these two sensor
circuits and discontinues the throttle control. At this time, the vehicle can be driven within its idling
range.

ECM

Accelerator Pedal Close by

Position Sensor Return Spring

Main
Sub Main
Sub
Throttle
Throttle Throttle Return Control
Position Valve Spring Motor
Sensor

Accelerator Pedal Throttle Body

199EG46

Downloaded from www.Manualslib.com manuals search engine

 EG-40 ENGINE - 1NZ-FE ENGINE

Fail-Safe of Throttle Position Sensor

 The throttle position sensor is comprised of two (main, sub) sensor circuits. If a malfunction occurs in
either one or both of the sensor circuits, the ECM detects the abnormal signal voltage difference between
these two sensor circuits, cuts off the current to the throttle control motor, and switches to the limp mode.
Then, the force of the return spring causes the throttle valve to return and stay at the prescribed opening
angle. At this time, the vehicle can be driven in the limp mode while the engine output is regulated
through the control of the fuel injection (intermittent fuel-cut) and ignition timing in accordance with the
accelerator opening.
 The same control as above is effected if the ECM detects a malfunction in the throttle control motor
system.

Injectors ECM Ignition Coil

Accelerator Pedal Return to

Position Sensor Prescribed Angle

Main
Sub Main
Sub
Throttle Throttle
Throttle Return
Valve Control
Position Spring Motor
Sensor
Accelerator Pedal Throttle Body
199EG47

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-41

7. VVT-i (Variable Valve Timing-intelligent) System

General

The VVT-i system is designed to control the intake camshaft within a range of 40 (of Crankshaft Angle)
to provide valve timing that is optimally suited to the engine condition. This realizes proper torque in
all the speed ranges as well as realizing excellent fuel economy, and reducing exhaust emissions.

Camshaft Timing Oil Control Valve

Throttle Position
Sensor
Camshaft Position
Sensor
ECM

Engine Coolant
Temperature
Sensor
Mass Air
Flow Meter

Crankshaft Position Sensor

247EG23

Using the engine speed signal, vehicle speed signal, and the signals from mass air flow meter, throttle
position sensor and water temperature sensor, the engine ECU can calculate optimal valve timing for
each driving condition and controls the camshaft timing oil control valve. In addition, the engine ECU
uses signals from the camshaft position sensor and crankshaft position sensor to detect the actual valve
timing, thus providing feedback control to achieve the target valve timing.

Camshaft
Crankshaft Position Sensor Timing
Target Valve Timing Oil
Duty-cycle control
Mass Air Flow Meter Valve
Control
Throttle Position Sensor Feedback

Engine Coolant Temp. Sensor Correction

Camshaft Position Sensor Actual Valve Timing

Vehicle Speed Sensor

221EG16

Downloaded from www.Manualslib.com manuals search engine

 EG-42 ENGINE - 1NZ-FE ENGINE

Effectiveness of the VVT-i System

Operation State Objective Effect

TDC
Latest Timing

Stabilized idling

During Idling Eliminating overlap to reduce rpm
EX IN

At Light Load blow back to the intake side
Better fuel
economy

BDC 188EG51

to Advance Side

Increasing overlap to increase
Better fuel

economy
At medium Load EX IN internal EGR to reduce pumping
Improved
loss
emission control

227EG40

to Advance Side

In Low to Advancing the intake valve Improved torque in

Medium Speed
Range with EX IN close timing for volumetric low to medium
efficiency improvement speed range
Heavy Load

227EG40

In High Speed Retarding the intake valve close

Range with EX IN timing for volumetric efficiency Improved output
Heavy Load improvement

to Retard Side 287EG34

Latest Timing
Eliminating overlap to prevent

Stabilized fast
blow back to the intake side
At Low idle rpm
Temperature EX IN leads to the lean burning
Better fuel
condition, and stabilizes the
economy
idling speed at fast idle
188EG51

Latest Timing

Upon Starting
Eliminating overlap to reduce Improved

Stopping the EX IN
blow back to the intake side startability
Engine

188EG51

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-43

Construction

1) VVT-i Controller
This controller consists of the housing driven from the timing chain and the vane coupled with the intake
camshaft.
The oil pressure sent from the advance or retard side path at the intake camshaft causes rotation in the
VVT-i controller vane circumferential direction to vary the intake valve timing continuously.
When the engine is stopped, the intake camshaft will be in the most retarded state to ensure startability.
When hydraulic pressure is not applied to the VVT-i controller immediately after the engine has been
started, the lock pin locks the movement of the VVT-i controller to prevent a knocking noise.

Intake Camshaft
Housing Lock Pin

Vane (Fixed on Intake Camshaft)

Oil Pressure

At a Stop In Operation 169EG36

Lock Pin

2) Camshaft Timing Oil Control Valve

This camshaft timing oil control valve controls the spool valve position in accordance with the duty-cycle
control from the ECM. This allows hydraulic pressure to be applied to the VVT-i controller advance or
retard side. When the engine is stopped, the camshaft timing oil control valve is in the most retarded state.

to VVT-i Controller to VVT-i Controller

(Advance Side) (Retard Side)

Sleeve

Spring

Plunger
Drain Drain Coil

Spool Valve
Oil Pressure 221EG17

Downloaded from www.Manualslib.com manuals search engine

 EG-44 ENGINE - 1NZ-FE ENGINE

Operation

1) Advance
When the camshaft timing oil control valve is operated as illustrated below by the advance signals from
the ECM, the resultant oil pressure is applied to the timing advance side vane chamber to rotate the
camshaft in the timing advance direction.

Vane

ECM

Rotation Direction
IN Drain
198EG35
Oil Pressure

2) Retard
When the camshaft timing oil control valve is operated as illustrated below by the retard signals from
the ECM, the resultant oil pressure is applied to the timing retard side vane chamber to rotate the camshaft
in the timing retard direction.

Vane

ECM

Rotation Direction
Drain IN
198EG36
Oil Pressure

3) Hold
After reaching the target timing, the valve timing is held by keeping the camshaft timing oil control valve
in the neutral position unless the traveling state changes.
This adjusts the valve timing at the desired target position and prevents the engine oil from running out
when it is unnecessary.

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-45

8. Fuel Pump Control

A fuel cut control is used to stop the fuel pump when the SRS airbag is deployed at the front, side or rear side
collision.
In this system, the airbag deployment signal from the airbag assembly is detected by the ECM, and it turns
OFF the circuit opening relay.
After the fuel cut control has been activated, turning the ignition switch from OFF to ON cancels the fuel cut
control, thus can be restarted.

From Battery

Circuit
Opening
Front Airbag Airbag Relay
Sensor Sensor ECM
(RH and LH) Assembly

Fuel Pump
Motor
Curtain Shield
Airbag Sensor Side Airbag
Assembly* Sensor Assembly*
(RH and LH) (RH or LH)

: CAN
00REG18Y

*: Option Equipment

Downloaded from www.Manualslib.com manuals search engine

 EG-46 ENGINE - 1NZ-FE ENGINE

9. Evaporative Emission Control System

General
The evaporative emission control system prevents the vapor gas that is created in the fuel tank from being
released directly into the atmosphere.
 The canister stores the vapor gas that has been created in the fuel tank.
 The ECM controls the purge VSV in accordance with the driving conditions in order to direct the vapor
gas into the engine, where it is burned.
 In this system, the ECM checks the evaporative emission leak and outputs DTC (Diagnostic Trouble
Codes) in the event of a malfunction. An evaporative emission leak check consists of an application of
a vacuum pressure to the system and monitoring the changes in the system pressure in order to detect a
leakage.
 This system consists of the purge VSV, canister, refueling valve, canister pump module, and ECM.
 The ORVR (Onboard Refueling Vapor Recovery) function is provided in the refueling valve.
 The canister pressure sensor has been included to the canister pump module.
 The canister filter has been provided on the fresh air line. This canister filter is maintenance-free.
 The followings are the typical conditions for enabling an evaporative emission leak check:

 Five hours have elapsed after the engine has been turned OFF*.
 Altitude: Below 2400 m (8000 feet)
Typical Enabling  Battery voltage: 10.5 V or more
Condition  Ignition switch: OFF
 Engine coolant temperature: 4.4 to 35C (40 to 95F)
 Intake air temperature: 4.4 to 35C (40 to 95F)
*: If engine coolant temperature does not drop below 35C (95F), this time should be extended to 7 hours.
Even after that, if the temperature is not less than 35C (95F), the time should be extended to 9.5 hours.

Service Tip
The canister pump module performs fuel evaporative emission leakage check. This check is done
approximately five hours after the engine is turned off. So you may hear sound coming from
underneath the luggage compartment for several minutes. It does not indicate a malfunction.
 The pinpoint pressure test procedure is carried out by pressurizing the fresh air line that runs from
the pump module to the air filler neck. For details, see the 2006 Yaris Repair Manual (Pub. No.
RM00R0U).

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-47

System Diagram

To Intake Manifold
Refueling Valve

Purge VSV

Fuel Tank Canister Pump Module

Canister Filter Vent

Purge Air
Valve
Line
Fresh Air Line M
Leak Detection
ECM Pump & Pump
Motor
P
Canister Canister
Pressure Sensor
00REG22Y

Function of Main Components

Component Function
Contains activated charcoal to absorb the vapor gas that is created in
Canister
the fuel tank.
Controls the flow rate of the vapor gas from the fuel tank to the canister
Refueling when the system is purging or during refueling.
Valve Restrictor Prevents a large amount of vacuum during purge operation or system
Passage monitoring operation from affecting the pressure in the fuel tank.
Fresh air goes into the canister and the cleaned drain air goes out into
Fresh Air Line
the atmosphere.
Opens and closes the fresh air line in accordance with the signals from
Vent Valve
the ECM.
C it
Canister
Leak Detection Applies vacuum pressure to the evaporative emission system in
Pump
Pump accordance with the signals from the ECM.
Module
Canister Detects the pressure in the evaporative emission system and sends the
Pressure Sensor signals to the ECM.
Opens in accordance with the signals from the ECM when the system
is purging, in order to send the vapor gas that was absorbed by the
Purge VSV
canister into the intake manifold. In system monitoring mode, this
valve controls the introduction of the vacuum into the fuel tank.
Canister Filter Prevents dust and debris in the fresh air from entering the system.
Controls the canister pump module and purge VSV in accordance with
the signals from various sensors, in order to achieve a purge volume
ECM
that suits the driving conditions. In addition, the ECM monitors the
system for any leakage and outputs a DTC if a malfunction is found.

Downloaded from www.Manualslib.com manuals search engine

 EG-48 ENGINE - 1NZ-FE ENGINE

Construction and Operation

1) Refueling Valve
The refueling valve consists of chamber A, chamber B, and the restrictor passage. A constant
atmospheric pressure is applied to chamber A.
 During refueling, the internal pressure of the fuel tank increases. This pressure causes the refueling
valve to lift up, allowing the fuel vapors to enter the canister.
 The restrictor passage prevents the large amount of vacuum that is created during purge operation or
system monitoring operation from entering the fuel tank, and limits the flow of the vapor gas from the
fuel tank to the canister. If a large volume of vapor gas recirculates into the intake manifold, it will
affect the air-fuel ratio control of the engine. Therefore, the role of the restrictor passage is to help
prevent this from occurring.

Chamber A
Fresh Air Line

Refueling
Valve (Open)
Chamber B Canister
From Fuel To Fuel
Tank Tank
Positive Pressure
Internal Pressure (Fuel Tank Pressure) Negative Pressure
Restrictor Passage (Intake Manifold Pressure)
During Refueling During Purge Operation or
System Monitoring Operation
285EG76 D13N07

2) Fuel Inlet (Fresh Air Line)

In accordance with the change of structure of the evaporative emission control system, the location of
a fresh air line inlet has been changed from the air cleaner section to the near fuel inlet. The flesh air from
the atmosphere and drain air cleaned by the canister will go in and out of the system through the passage
shown below.
Fuel Tank Cap
Fresh Air

To Canister

Cleaned Drain Air

Fuel Inlet Pipe
228TU119

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-49

3) Canister Pump Module

Canister Pump module consists of the vent valve, leak detection pump, and canister pressure sensor.
 The vent valve switches the passages in accordance with the signals received from the ECM.
 A DC type brush less motor is used for the pump motor.
 A vane type vacuum pump is used.

Vent Valve
Canister
Pressure Sensor Fresh Air

Leak Detection Pump

 Pump Motor
Fresh Air
 Vane Pump

Canister
Pressure Sensor
Canister
279EG25 279EG26

Simple Diagram 

Canister Pump Module

Vent Valve
Fresh Air
Filter Filter
M To Canister
Leak Detection Pump
& Pump Motor
P
Filter
Canister
Pressure Sensor
Reference Orifice
[0.5 mm, (0.020 in) Diameter]
D13N17

Downloaded from www.Manualslib.com manuals search engine

 EG-50 ENGINE - 1NZ-FE ENGINE

System Operation
1) Purge Flow Control
When the engine has reached predetermined parameters (closed loop, engine coolant temperature above
74C (165F), etc.), stored fuel vapors are purged from the canister whenever the purge VSV is opened
by the ECM.
The ECM will change the duty ratio cycle of the purge VSV, thus controlling purge flow volume. Purge
flow volume is determined by intake manifold pressure and the duty ratio cycle of the purge VSV.
Atmospheric pressure is allowed into the canister to ensure that purge flow is constantly maintained
whenever purge vacuum is applied to the canister.
To Intake Manifold
Atmosphere

Purge VSV
(Open)

ECM

00REG23Y

2) ORVR (On-Board Refueling Vapor Recovery)

When the internal pressure of the fuel tank increases during refueling, this pressure causes the diaphragm
in the refueling valve to lift up, allowing the fuel vapors to enter the canister. Because the vent valve is
always open (even when the engine is stopped) when the system is in a mode other than the monitoring
mode, the air that has been cleaned through the canister is discharged outside the vehicle via the fresh
air line. If the vehicle is refueled in the monitoring mode, the ECM will recognize the refueling by way
of the canister pressure sensor, which detects the sudden pressure increase in the fuel tank, and will open
the vent valve.
Open

Close

00REG24Y

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-51

3) EVAP Leak Check

a. General
The EVAP leak check operates in accordance with the following timing chart:

Timing Chart 

Purge ON (Open)
VSV OFF (Close)
Vent ON
Valve OFF (Vent)
ON
Pump Motor
OFF

Atmospheric Pressure

System
Pressure
0.02 in. Pressure

1) 2) 3) 4) 5)
D13N20

Order Operation Description Time

Atmospheric Pressure ECM turns vent valve OFF (vent) and measures EVAP
1) 10 sec.
Measurement system pressure to memorize atmospheric pressure.
Leak detection pump creates negative pressure
0.02 in. Leak
(vacuum) through 0.02 in. orifice and the pressure is
2) Pressure 60 sec.
measured. ECM determines this as 0.02 in. leak
Measurement
pressure.
Leak detection pump creates negative pressure
(vacuum) in EVAP system and EVAP system pressure
is measured. If stabilized pressure is larger than 0.02 in. Within
3) EVAP Leak Check
leak pressure, ECM determines EVAP system has a 12 min.
leakage. If EVAP pressure does not stabilize within 12
minutes, ECM cancels EVAP monitor.
ECM opens purge VSV and measure EVAP pressure
4) Purge VSV Monitor increase. If increase is large, ECM interprets this as 10 sec.
normal.
ECM measures atmospheric pressure and records
5) Final Check
monitor result.

Downloaded from www.Manualslib.com manuals search engine

 EG-52 ENGINE - 1NZ-FE ENGINE

b. Atmospheric Pressure Measurement

1) When the ignition switch is turned OFF, the purge VSV and vent valve are turned OFF. Therefore,
the atmospheric pressure is introduced into the canister.
2) The ECM measures the atmospheric pressure through the signals provided by the canister pressure
sensor.
3) If the measurement value is out of standards, the ECM actuates the leak detection pump in order to
monitor the changes in the pressure.
Atmosphere

Purge VSV
(OFF)

Canister Pump Module

Vent Valve
(OFF)

M
Leak Detection Pump
ECM & Pump Motor
P
Canister
Pressure Sensor
00REG25Y

ON (Open)
Purge VSV
OFF (Close)
ON
Vent Valve
OFF (Vent)
ON
Pump Motor
OFF

Atmospheric Pressure

System Pressure

D13N22
Atmospheric Pressure Measurement

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-53

c. 0.02 in. Leak Pressure Measurement

1) The vent valve remains off, and the ECM introduces atmospheric pressure into the canister and
actuates the leak detection pump in order to create a negative pressure.
2) At this time, the pressure will not decrease beyond a 0.02 in. pressure due to the atmospheric pressure
that enters through a 0.02 in. diameter reference orifice measuring 0.5 mm (0.02 in.).
3) The ECM compares the logic value and this pressure, and stores it as a 0.02 in. leak pressure in its
memory.
4) If the measurement value is below the standard, the ECM will determine that the reference orifice
is clogged and store DTC (Diagnostic Trouble Code) P043E in its memory.
5) If the measurement value is above the standard, the ECM will determine that a high flow rate pressure
is passing through the reference orifice and store DTCs (Diagnostic Trouble Codes) P043F, P2401,
P2402, and P2422 in its memory.

Atmosphere

Purge VSV
(OFF)

Canister Pump Module

Vent Valve
(OFF)

M
Leak Detection
ECM Pump & Pump
Motor
P
Canister Pressure
Sensor
Reference Orifice 00REG26Y

ON (Open)
Purge VSV
OFF (Close)
ON
Vent Valve
OFF (Vent)
ON
Pump Motor
OFF

Atmospheric Pressure

System Pressure

0.02 in. Pressure

0.02 in. Pressure Measurement D13N26

Downloaded from www.Manualslib.com manuals search engine

 EG-54 ENGINE - 1NZ-FE ENGINE

d. EVAP Leak Check

1) While actuating the leak detection pump, the ECM turns ON the vent valve in order to introduce a
vacuum into the canister.
2) When the pressure in the system stabilizes, the ECM compares this pressure and the 0.02 in. pressure
in order to check for a leakage.
3) If the detection value is below the 0.02 in. pressure, the ECM determines that there is no leakage.
4) If the detection value is above the 0.02 in. pressure and near atmospheric pressure, the ECM
determines that there is a gross leakage (large hole) and stores DTC P0455 in its memory.
5) If the detection value is above the 0.02 in. pressure, the ECM determines that there is a small leakage
and stores DTC P0456 in its memory.

Atmosphere

Purge VSV
(OFF)

Canister Pump Module

Vacuum
Vent Valve
(ON)

M
Leak Detection
ECM Pump & Pump
Motor
P
Canister
Pressure Sensor Reference Orifice

00REG27Y

OFF (Close)
Purge VSV
ON (Open)
ON
Vent Valve
OFF (Vent)

Pump Motor ON
OFF

P0455
Atmospheric Pressure

System Pressure P0456

0.02 in. Pressure

Normal

EVAP Leak Check D13N62

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-55

e. Purge VSV Monitor

1) After completing an EVAP leak check, the ECM turns ON (open) the purge VSV with the leak
detection pump actuated, and introduces the atmospheric pressure from the intake manifold to the
canister.
2) If the pressure change at this time is within the normal range, the ECM determines the condition to
be normal.
3) If the pressure is out of the normal range, the ECM will stop the purge VSV monitor and store DTC
P0441 in its memory.

Atmosphere
Atmosphere

Purge VSV
(ON)

Canister Pump Module

Vent Valve
(ON)

M
Leak Detection
ECM Pump & Pump
Motor
P
Canister
Pressure Sensor
00REG28Y

ON (Open)
Purge VSV
OFF (Close)

Vent Valve ON
OFF (Vent)
ON
Pump Motor
OFF

Atmospheric Pressure

Normal
System Pressure

0.02 in. Pressure

P0441

D13N63
Purge VSV Monitor

Downloaded from www.Manualslib.com manuals search engine

 EG-56 ENGINE - 1NZ-FE ENGINE

10. Cooling Fan Control

 On the models without air conditioning, the ECM controls the operation of the cooling fan based on the
engine coolant temperature sensor signal.

Wiring Diagram 

Cooling Fan Relay No.1

Cooling Fan Motor

Engine Coolant ECM
Temperature Sensor
Cooling Fan Relay No.2

00SEG47Y

Cooling Fan Operation 

Engine Coolant Temperature Low High
Cooling Fan Operation OFF ON
 On the models with air conditioning, the ECM controls the operation of the cooling fan in two speeds (Low
and Hi) based on the engine coolant temperature sensor signal and the A/C ECU signal.
The Low speed operation is accomplished by applying the current through a resistor, which reduces the
speed of the cooling fan.

Wiring Diagram 

Cooling Fan Relay No.1

Engine Coolant
Temperature Sensor
Cooling Fan Motor
ECM
A/C ECU Cooling Fan Relay No.2

Resistor
(Low Speed Operation)
: CAN 00SEG48Y

Cooling Fan Operation 

Engine Coolant Air Conditioning Condition
Cooling Fan Operation
Temperature*1 A / C Switch Refrigerant Pressure*2
OFF Low OFF
Low ON Low Low
ON High High
OFF Low High
High
g ON Low High
ON High High

*1: Judgmental standard of engine coolant temperature *2: Judgmental standard of refrigerant pressure
High High

Low Low
94.5C 96C 1.2 MPa 1.5 MPa
(12.5 kgf/cm2, 178 psi) (15.5 kgf/cm2, 220 psi)
(202.1F) (204.8F) 00SEG81Y

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-57

11. Cranking Hold Function

General
 Once the ignition switch is turned to the START position, this control continues to operate the starting
until the engine starts, without having to hold the ignition switch in the START position. This prevents
starting failures and the engine from being cranked after the engine has started.
 When the ECM detects a start signal from the ignition switch, this system monitors the engine speed (NE)
signal and continues to operate the starter until it determines that the engine has started.

System Diagram 

ACC Cut Relay ECM

ACCR

Ignition Switch
STSW

Ignition Switch STAR

 Park/Neutral
Position
Switch*1
Starter  Clutch Start
Switch*2

STA

Starter
Battery Relay
 Engine Speed Signal
 Engine Coolant
Temperature Signal
00SEG55Y

*1: for Automatic Transaxle Models

*2: for Manual Transaxle Models

Downloaded from www.Manualslib.com manuals search engine

 EG-58 ENGINE - 1NZ-FE ENGINE

Operation
 As indicated in the following timing chart, when the ECM detects a start signal from the ignition switch,
it energizes the starter relay to operate the starter. If the engine is already running, the ECM will not
energize the starter relay.
 After the starter operates and the engine speed becomes higher than approximately 500 rpm, the ECM
determines that the engine has started and stops the operation of the starter.
 If the engine has any failure and does not work, the starter operates as long as its maximum continuous
operation time and stops automatically. The maximum continuous operation time is approximately 2
seconds through 25 seconds depending on the engine coolant temperature condition. When the engine
coolant temperature is extremely low, it is approximately 25 seconds and when the engine is warmed up
sufficiently, it is approximately 2 seconds.
 In case that the starter begins to operate, but cannot detect the engine speed signal, the ECM will stop
the starter operation immediately.

Timing Chart 

START
Ignition Switch
Position
ON
Cranking Limit
Approx. 2 - 25 sec.
ON

Starter Relay
OFF
ON
Accessory Power OFF
Successful
Starting of Engine

Engine Speed Signal Failed Starting of

(NE) Engine

ECM determines that the engine has started

successfully when the engine speed is
approximately 500 rpm.
00SEG57Y

Downloaded from www.Manualslib.com manuals search engine

 ENGINE - 1NZ-FE ENGINE EG-59

12. Diagnosis

When the ECM detects a malfunction, the ECM makes a diagnosis and memorizes the failed section.
Furthermore, the MIL (Malfunction Indicator Lamp) in the combination meter illuminates or blinks to
inform the driver.

The ECM will also store the DTCs of the malfunctions.

The DTCs can be accessed by the use of the hand-held tester.

To comply with the OBD-II regulations, all the DTCs (Diagnostic Trouble Codes) have been made to
correspond to the SAE controller codes. Some of the DTCs have been further divided into smaller
detection areas than in the past, and new DTCs have been assigned to them. For details, refer to the 2006
Yaris Repair Manual (Pub. No. RM00R0U).

Service Tip
To clear the DTC that is stored in the ECM, use a hand-held tester or disconnect the battery terminal
or remove the EFI fuse for 1 minute or longer.

13. Fail-Safe
When a malfunction is detected at any of the sensors, there is a possibility of an engine or other malfunction
occurring if the ECM were to continue to control the engine control system in the normal way. To prevent
such a problem, the fail-safe function of the ECM either relies on the data stored in memory to allow the
engine control system to continue operating, or stops the engine if a hazard is anticipated. For details, refer
to the 2006 Yaris Repair Manual (Pub. No. RM00R0U).

Downloaded from www.Manualslib.com manuals search engine

 EG-60

- MEMO -

Downloaded from www.Manualslib.com manuals search engine