my cars a 2001 Camaro ss 6speed
mods
ps-1 pro charger full kit I just installed last year , GMMG exhaust
rest is all stock

I recently got a check engine light p0171 p0174 lean both banks, check for any vacuum leaks and found none , but I replaced my pcv hose just incase , still got the code after driving 10-20 miles, then hooked up a fuel pressure gauge at the fuel rail, I was getting 52psi ignition on car off, start the car 58-60 psi, then drove around and notice at wot under boost fuel pressure would drop to 35-40psi.
so I took out the dw250 inline pump that pro charger provided and install a quantum 340lph whole new unit and casper Hotwire kit, and new fuel filter, the old one had gunk and rubber **** inside when I drained it not sure how it got inside, but now my fuel pressure is 68-70psi when cars running and when wot fuel drops to 58-60psi under boost, quantum said it was normal their pumps run max 60-70 psi but the regulator will compensate to what I need if factory setting is 58psi is this correct ?

another issue when cars off psi at fuel rail is 52psi it will hold that pressure for a few hours then taper off to around 30psi then over night next morning will be at 0 psi is this normal ? and do I need to retune the car now ? just has the base tune pro charger sent me.

car runs good no issues , air fuel guage is at 14.7 at idle and 11-11.5 at wot

 

It does not need to hold pressure when off. Even if it dropped to zero on shutoff it is not an issue.
58-60psi is rated pressure at the injector. If you have that all is good. The new pump fixed it.

 

ok cool, so as long as when I turn off the car and the fuel pressure doesn't drop like super fast within second or minutes to 0 then its fine? reading things online some people say their ls1 cars hold 58psi all night long, so I was a bit worried.

 

but if the fuel pressure drops super fast like with in seconds or minutes when the cars off then thats and issue right, like stuck open fuel injector or bad regulator ?

 

It's natural for pressure to bleed off after shutdown. As long as it pressures up when the key is on you're in business. Don't sweat over what-ifs...

 

You should install a boost referenced FPR when running a forced induction setup. You must remove the in-tank regulator when installing the external FPR. The stock in-tank regulator maintains a static 58 psi at all times - ok for a stock fuel system setup. It should be removed for forced induction.

If you have a Corvette fuel filter/fuel pressure regulator it maintain a static 58 psi of fuel pressure. It will not increase fuel pressure when under boost. Remove it and install a standard filter with specs necessary to provide the additional fuel flow requirements due to forced induction.

Under boost, the external FPR will increase fuel pressure on a 1:1 basis as boost increases. If you make 8lbs of boost the FPR will mechanically increase fuel and pressure from 58 psi + 8 psi = 66 psi that is required inside the rail. Your fuel pressure gauge should read 66 psi when making 8 lbs of boost.

You set the external FPR at idle at 58 psi with the vacuum line at the FPR disconnected. Read the FPR instructions.

After setting the FPR at idle, reinstall the intake vacuum line at the FPR. After attaching the vacuum line, the FPR will reduce fuel pressure on the inside of the rails and tip of each injector based on the inches of intake vacuum at idle. Most times somewhere near 42-43 on the gauge (58 psi - inches of intake vacuum = gauge setting (fuel pressure) at idle.

To test - remove the vacuum line or the pinch the vacuum line - fuel pressure will increase to 58 psi. Attach the vacuum line. Fuel pressure will drop accordingly based on inches of vacuum at idle.

You also need to make sure that you install a check valve in the vacuum line near the TB. The check valve stops boost leak when vacuum inside the intake transitions from vacuum to boost pressure.