Car is 77 280z
So I've been looking into why my fuel pressure drops to 0 after shut down relatively fast from almost instantly to about 30 minuets. After some testing I found that sometimes the stock fpr was stuck open and let the gas bypass into the return and sometimes it would drip slowly taking a bit longer, but ultimately to 0.
So I have tried two stock replacements one from autozone and one from Napa, they both let the gas bleed through after shutdown, I know because I removed the return line and used a clear line for the testing, I would prime the fuel pump to build pressure and it will go to 0 in about 15 minuets and I can see the line with gas in it.
My question is, are the aftermarket stock replacement ones not supposed to hold pressure at least overnight?
My cold start injector and injectors do not leak I have pulled them to observe during the leak down, my fuel pump is new and I have an inline check valve. Thanks!
Other than that it runs great, about 30 idle, 40with th vac unplugged.