My fuel rail doesn't hold pressure

[kevinkay]

My car starts perfect when cold, perfect when HOT, (with in short time of shutting off), but is harder to start when warm - like 1/2 hour to an hour after turning off, engine cranks but doesn't catch unless I pump accelerator pedal.

I have replaced all the O rings and did my best to clean the injectors (compressed air, brake cleaner and 12 volts). When reading instructions to remove the fuel rail and did not get gas discharge at the schrader valve I was a bit concerned , but hoping the leak was an O ring. So, still the hard start at warm and little or no pressure at the valve after car sits.

I am assuming one of the injectors is leaking/bad. I am thinking I should get 1 new injector and rotate it though the 6 until my symptoms go away? Is there any other way to check injections without fancy shop equipment?

OR do I look to the fuel pressure regulator? (not even sure where that is)!!

Thanks!

[jdstrickland]

My money is on the regulator. It can leak down, and the fuel remains within the system. If an injector was leaking, then the car would run poorly because it would leak at undesirable times. Think about it, the injector will leak when there is pressure on the system, it will result in the cylinder running rich where the leaking injector is. If the regulator leaks down, then you would have trouble with any starts, not just warm ones. You said that there was no fuel coming out of the Schrader valve with engine off, I would wonder about the pressure regulator first.

[kevinkay]

I get fuel and pressure from the Schrader valve when first shut off and probably for about and hour. After it sits over time there is only a quick "hiss" and no gas discharge from the valve.

Where is the regulator?

[kvc]

Regulator is incorporated in fuel filter/pump. At 175K+ mileage, my money is on the fuel filter/pump/regulator, unless you've already had that changed over.