swathdiver
Full Access Member
Maybe the old owner replaced the fuse block with one from another year?
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
Your truck didn’t come with a fuel pump relay. The combination of FPCM (aka Fuel Pump Drive Module), Fuel Pressure Sensor and PCM, control power to your fuel pump and regulate fuel pressure to the rail.
I suspect what is happening is by populating that relay, you are turning power on to the pump when the key is on, but you may have no pressure regulation, just on full pump pressure.
Is there a way to test the fcmp module.I have to go do some research but I don’t think your model year came with a relay in that position, I think it is normal to be unpopulated.
It may indicate you have an issue elsewhere, like your FPCM, pressure sensor or again your pump.
I will go see if my supposition is correct and get back.
unless the ones that work on ppv vehicles did it. It was a border patrol vehicle.Maybe the old owner replaced the fuse block with one from another year?
There is a way to exercise the FPCM/Fuel pump and monitor fuel pressure, but it takes a Tech 2.Is there a way to test the fcmp module.
unless the ones that work on ppv vehicles did it. It was a border patrol vehicle.
I don’t see any cut wires. I know now that the fuel module has been replaced at on time. The part in it is a dorman part.There's no telling what was done to a police vehicle. I worked on a police suburban many years ago that had constant intermittent issues. Couldn't believe the mess of wires. Cut wires all over the place. Devices still partially hooked up, etc. Took he several days on and off to get everything removed that wasn't original. Patched numerous wires. Reattached numerous more wires. Got luck and when I was done, everything worked properly and no more intermittent issues.