I've been running into a recurring issue where the car has been cutting out, losing power, and eventually stalling out. I am able to immediately start up the car again, get full fuel pressure (30-40psi), and then it falls off and stalls. As a strange side effect, my left turn signal indicator light turns on, but doesn't blink.
Sometimes, after a few attempts, the issue goes away and I am able to drive off like normal. Sometimes it happens after the car is warmed up completely and I've been driving for a while, and sometimes, it happens within a few minutes of starting the car. But this morning, the issue kept persisting.
It's clearly a fuel pressure issue. The question is, what's causing the fuel pressure to cut out randomly.
I just changed the fuel filter a few months ago.
I have a Walbro 255 LPH pump which was installed 5 or 6 years ago. I also have 42LB injectors. I haven't changed any wiring with the fuel system.
I'm thinking it could be perhaps a clogged fuel sock, or maybe a fuel pump driver module.
As a side note, I've been having a parasitic voltage drain, where the battery will die after the car has been sitting after a few days. It's not the GEM module, because I've pulled that fuse and the issue persists. So, I'm thinking maybe the fuel issue and the voltage issue are connected. Maybe the FPDM is what's pulling voltage.
I've also been battling the dreaded p0171 p0174 lean codes in both banks for the past few years, but that has been such an ongoing issue, I think it's a vacuum leak or something rather than a fuel pump issue.
Under normal operation, I get around 30 psi of fuel pressure, all the way up to 55-60 psi under throttle according to my Auto Meter gauge.
Is the FPDM on all 99-04 mustangs interchangeable? What about from other fords, such as Crown Vics, V8 explorers, Navigators, whatever? I could just go to the Junkyard, pick one up and see if that fixes the issue. Or, I could always just go to the parts store, pick up a new one, and return it if that doesn't fix the problem.
Is there any other electrical component or box besides the FPDM that I should be worried about?
Has anyone experienced any fuel pressure issues such as this before?
Homer
Sometimes, after a few attempts, the issue goes away and I am able to drive off like normal. Sometimes it happens after the car is warmed up completely and I've been driving for a while, and sometimes, it happens within a few minutes of starting the car. But this morning, the issue kept persisting.
It's clearly a fuel pressure issue. The question is, what's causing the fuel pressure to cut out randomly.
I just changed the fuel filter a few months ago.
I have a Walbro 255 LPH pump which was installed 5 or 6 years ago. I also have 42LB injectors. I haven't changed any wiring with the fuel system.
I'm thinking it could be perhaps a clogged fuel sock, or maybe a fuel pump driver module.
As a side note, I've been having a parasitic voltage drain, where the battery will die after the car has been sitting after a few days. It's not the GEM module, because I've pulled that fuse and the issue persists. So, I'm thinking maybe the fuel issue and the voltage issue are connected. Maybe the FPDM is what's pulling voltage.
I've also been battling the dreaded p0171 p0174 lean codes in both banks for the past few years, but that has been such an ongoing issue, I think it's a vacuum leak or something rather than a fuel pump issue.
Under normal operation, I get around 30 psi of fuel pressure, all the way up to 55-60 psi under throttle according to my Auto Meter gauge.
Is the FPDM on all 99-04 mustangs interchangeable? What about from other fords, such as Crown Vics, V8 explorers, Navigators, whatever? I could just go to the Junkyard, pick one up and see if that fixes the issue. Or, I could always just go to the parts store, pick up a new one, and return it if that doesn't fix the problem.
Is there any other electrical component or box besides the FPDM that I should be worried about?
Has anyone experienced any fuel pressure issues such as this before?
Homer
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