replaced the fuel regulator yesterday afternoon, still only getting 35 PSI on the fuel rail. New fuel pump, filter, regulator, no visible damage or wear on the fuel lines, and I'm still only getting 35 PSI. Please, anyone have any ideas as to what may be causing this?

 

Post #4 , but that's how it goes sometimes. Engine OFF key ON , called EOKO. Try clamping the rubber return fuel line back at the tank and see if the static pressure goes above 43psi. Then if it does not hold high pressure it's possibly the small rubber hose inside the tank connected to the pump that could be cracked, dislodged, leaking or missing, like a check valve. This is called dead head pressure.

You said the fuel pump has been replaced, wonder why? Did you check the voltage or amp draw on the pump? Old and new?

How much fuel is in the tank? Is it more than a quarter tank?

Does the engine have to crank a lot when starting? I assume its not firing right up like it should.

Have you OHM tested the fuel injectors? No? you will need to do it. Even if they check out okay further testing may be needed to check for a leaking injector (stuck open). Temperature will effect the ohm reading, do them all at once (cold and then hot) is good practice.

Try this test real quick, unplug the vacuum line at the regulator, do you see any wet fuel or smell strong vapors inside the hose? If so the "new" regulator could be defective. Can't trust the made in China stuff much these days.

Make sure that the small plastic black cone shaped vacuum diaphram near the regulator (passnger side on my '93) isn't cracked if your car has one. LOOK at the BACK of it...it may appear on the front as good but they can split open in the back where you can't see it installed! Get a vacuum pump and test it off of the car. Replace if necessary.

Report your findings. Parts chasing is not the way to solve an issue. Find the evidence to the problem then repair. Good luck

 

Appreciate the reply. Spent the day working on it and talking with some of the guys I'll be racing with. After all the trouble shooting, it seems the regulator I got from advance was bad. Got a different brand name regulator and the appears to be running right now. No codes and no stuttering when pedal is floored

 

"Try this test real quick, unplug the vacuum line at the regulator, do you see any wet fuel or smell strong vapors inside the hose? If so the "new" regulator could be defective. Can't trust the made in China stuff much these days."

Glad you got it fixed. Check out my youtube channel Ozzstar, you may like some of the repairs I do. Take it easy - Ozz