Fuel pressure after ignition key off, etc.

[Hink]

I have been checking thru some postings but no solid info yet. So thought would try starting a thread.On key off, my fuel pressure drops to 0 almost instantly. Some mechanic told me this might be the check ball on my in tank fuel pump. Could this cause any driveability issues?
Another possiblity maybe, fuel pressure rail has a aeromotive billet aluminum fuel pressure regulator. Could the regulator be causing the quick drop? Also am wondering if this is the correct regulator for a normally aspirated engine setup. On detaching the vac hose ,fuel pressure goes up to around 47 psi , vs 42 with engine running and vac hose connected.Still trying to eliminate issues on my car
TIA,
Hink

 

[HISSIN50]

Your mechanic is right about the check valve (no, other than prolonged cranking when it really goes south, it doesnt generally cause issues in and of itself). The FPR can definately cause a drop in pressure too (many aftermarket pieces seem to allow the pressure to drop almost immediately).

Your FPR sounds alright - that's about the right pressure delta. It's just that you're running a ton of pressure (most folks are at ~39 PSI with the vac line off).

Good luck.

 

[vristang]

I had been having the same trouble for some time and assumed it was the pump. I replaced my Aeromotive AFPR for the stock regulator and the pressure holds very well now.

As JT stated your fuel pressure is too high. Get down to the 38-40psi range.


jason

 

[Hink]

ok, still sorting things out here, adjusted the FPR for ~40 with vac hose off. Disconnected my battery for a while will see what happens, with my issues
on the car.
Thanks,
Hink