Hello, Scotty (Big Fan of your shows) I have a question about my 2003 Chevy Impala V6 3.8L 3800. it dies while driving at low speeds (down a driveway or in the parking lot). highway driving is fine. there is a constant cylinder 4 misfire code I've had since I've had the car. tried new ign coils, plugs, plug wires, new injectors, and new fuel filter. any ideas?