Fuel system question
 

While i had my 95 GT in my automechanics class shop i tested the fuel pressure and got 20 psi with KOEO. Then i got 30 psi KOER. I know the specs are 35-45 psi KOEO and 30-45 psi KOER. Would a bad regulator cause the KOEO reading? I forgot to pull the vacuum line when the engine was on to se what the pressure went up to. Also acouple times when i shut the engine off the fuel pressure would drop to 0. Sometimes it would stay at 20. Whats the deal with that? Also would 30 PSI cause a lean condition? Because thats how the car is running

anybody?

My car is detonating too. And I've had the fuel system suspect for a while. It just only detonates when it is hot out or when the car has been running a long time.

I don't have an answer for you though :(

My car does the same thing. It is only a problem if the fuel pressure drops to zero within seconds. The fuel can go 2 places. Past the injectors and into the cylinders, or by the regulator and back to the tank.

As far as key on, engine off fuel pressure, I would not worry too much about that. 30 psi with the engine running is normal and at WOT the pressure should rise to 38-40. You can also check WOT fuel pressure just disconnecting the vacuum line to the regulator while the engine is running.

Well the pressure doesnt drop in seconds it drops instantly when i turn the key off. But it only does it once in a while. Ive found out that acouple of the injectors were replaced and the rest were ultrasonicly cleaned, so i doubt the injectors as the problem.