Fuel Pressure
Thread Starter
Racer
Joined: Sep 2002
Posts: 420
Likes: 1
From: SAN DIEGO CA
Fuel Pressure
I was told to check the Fuel pressure to see if that was causing my Hot start problems. I hooked a fuel pressure guage and started the engine. The pressure held steady at 42 while the car was on. when I turned off the Engine the needle dropped to 30 in about 5 seconds. Then 10 seconds more it dropped to 22 psi. It stayed at 22 for about 1 minute then it started coming down to zero in about 3 minutes. I have Ford Injectors and I had them cleaned and pressure tested prior to installing them 6 months ago. I'm driving an 86 corvette with a 383 stroker putting out about 340 ponies. I have the ligenfelter intake Superram system with an adjustable fuel pressure regulator. So whats my next step? 
Drifting
Joined: Mar 2005
Posts: 1,923
Likes: 0
From: GA
Have someone turn the key on, as soon as the pump stops, crimp off the fuel feed line (vice grips work good for this, just mind the teeth on the jaws) . If it holds presssure, release the clamp, move the clamp to the return line and prime the pump again and clamp when the pump stops. If the pressure drops off now, it is the check valve in the pump. A bad chack valve can cause a little longer start time.
If it didn't hold pressure the first time, remove the vacuum line from the regulator, if there is fuel present there, the regulator is shot. If there isn't fuel, suspect an injector or more leaking.
If it didn't hold pressure the first time, remove the vacuum line from the regulator, if there is fuel present there, the regulator is shot. If there isn't fuel, suspect an injector or more leaking.
