Clark_rx7

Hey guys I need a little insight;

In the morning when the car is cold, when I energize the car the fuel pressures reads 0, after a crank or two it moves up to 20 which after that it fires up...when it starts running, the fuel pressure reads normal and acts accordingly. I dont have problems throughout the day til the next morning... but it seems like in the morning my engine has to draw in the fuel from the tank which then after the pump works fine. Is this a bad pump, or maybe a clogged filter needing the assistance of the vaccum of my engine cranking to clear through? ty

Clark_rx7

guess noone wants to tackle it

hanman

Possibilities:
leaking injector allow the system to depressurize

malfunctioning fuel pressure regulator

Clark_rx7

I went to a japanese auto shop, who btw say they refuse to work on 7's, for some advice. He said the same thing leaking injectors, but Id be flooding if that were the case, right? . So maybe its the check valve in the fuel pump, how does the regulator function?... They suggested clamping both the return and sending lines on the pump and wait awhile to see if my system depressurizes, if it doesnt then its the pump.

yuichiror

iTrader: (1)

Any fuel smell around the UIM toward the passenger side? Maybe a leaky FPD??