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2005 Honda Accord 3.0 V6 ex.......p0171 lean code bank 1.......tested EGR valve- passed, tested upstream and downstream 02 sensors-passed, fuel injectors all brand new-passed.....map sensor-passed......smoke tested- no vacuum leaks- passed, .....fuel pressure at idle 60 psi....once it shut the engine off it drops to 0 psi after 30 min, is this normal? Also can an injector stay partially open and cause it not to give sufficient fuel to the cylinder, and once the engine is turned off can it leak fuel back in to the cylinder, which might possibly be causing the fuel pressure drop as well? At this point I'm Not sure if I have a fuel pump, or a faulty Injector problem......
It's important to know when it's running lean to know how to proceed.
If it's lean @ idle and fine under load, then it's probably not a fuel delivery issue. The inverse is also true.
A check of freeze frame data will let you know when the code sets.
Check LTFT & STFT with upstream and downstream o2s @ park idle no load, park 2500rpm, steady cruise, and WOT pull through first gear.
I'm not super worried about the rate at which the fuel pressure drops in your case, unless most of that drop happens in the first moments you turn off the fuel pump.
Did you change the fuel injectors to correct the lean code, or did this problem come after the new injectors were installed?
If they are of the wrong flow rate, you can end up with a lean condition. Additionaly it's easy to mess up the O-rings while installing the injectors. This can give you a vacuum leak you probably won't see with a smoke typical low pressure machine.
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