Technical Bulletin #065
Transmission: A4LD
Subject: Lugs the engine
Application: Ford
Issue Date: August, 1991
A4LD
Lugs the Engine
Lugs the Engine When Coming to a Stop.
(The Torque Converter Clutch Won't Release.)
If you have an A4LD that lugs the engine when coming to a stop, you may have a TCC release problem. Use the
following steps to correct it.
STEP 1: Disconnect the lock-up cancel solenoid wires.
The converter clutch should not apply with the wires disconnected. If it does apply, go to Step 2. If it does not
apply, check for a shorted ground wire or a computer malfunction.
STEP 2: Make sure the check ball in Figure 1 is installed.
Figure 1
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Technical Bulletin #065
STEP 3: Make sure the solenoid isn't stuck.
With the solenoid de-energized, apply air in the end, (Figure 2) air should come out of hole "B". With the sole-
noid energized, air should come out of hole "A".
Figure 2
STEP 4: Enlarge the solenoid feed hole in the separator plate.
Enlarge the solenoid feed to 1/16". (Figure 3) If you have a spearator plate with a screen in the feed hole, leave
the hole alone, just make sure the screen is clean.
Figure 3
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Technical Bulletin #065
STEP 5: Make sure the valve body is flat.
Flat file the valve body to get rid of any high spots.
STEP 6: Replace the shuttle valve spring.
Replace the shuttle valve spring with a spring that weighs 6 pounds at .500". Figure 4.
Figure 4
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