The "Fetzer valve", when Lucinda the mechanic is giving the Sheriff her findings about Mona's car, she says the "Fetzer valve" had been punctured. A "Fetzer valve" is a fictional part of an engine, introduced in the movie Fletch (1985).
Every character's automobile has personalized plates.
The first thing to appear onscreen is a little blurb about the Yugo car company using the town of Verplanck as a test area for their new model years ago. Every vehicle in town that is not a truck is a Yugo, except the police cruisers, which are Plymouth Horizons. Not true! Valerie drives a newer modern truck, and Jeph and Bobby have a pick up truck for the landscaping business.
The character name, Wyatt Rash, was intentionally chosen by writer, Peter Steinfeld, to reflect the underlying premise of the movie -- said fast enough, it sounds like ... yup, White Trash!