Help i need help understanding how fuel pump relay stays energized on 2002 chevy expressi have lost secondary spark no spark at plugs. If it is stuck the pump could continue to run.
2003 2007 Cummins No Start No Problem Diesel Power
Fuel pump stays running. When you turn the ignition on even without starting the engine that activates the fuel pump and also pressurized the tank. Normally the fuel pump relay operates during starting and when turning off the engine. Combined with the other issues you stated its most likely the pcm. A fuel pump should pump all the time when the engine is running there maybe if its fuel injected a pressure regulator to ensure sufficient pressure is there otherwise it is. Suspect the fuel pump relay. Hello i have a 2008 sierra sle with a 53 engine.
When i turn the truck off the fuel pump continues to run. Sounds like the fuel pump relay in under hood fuse box try finding another next to it thats the same from the headlamp relay and swap them and see if it helps. Remove the connector the retainer screws then pull it out and open it. The only way i can get it. A full explanation of how the relay works and how to check it is quite long. I suggest you check the net for info on how a fuel pump relay works and conduct the electrical test.
Fuel pump fuse ecm 11 20 amp is blownis the fuel pump linked t. Look for signs of moisture burn marks or leaking capacitors. It sounds like you have a short to voltage somewhere. No its not the fuel pump thats running but the purging system. I swapped the ac compressor relay with the fuel pump relay in the fuse block but that did nothing. Now the transmission does not shift properly and the fuel pump seems to keep running.
I tried pulling the fuel pump fuse and it still kept running. Therefore the purging process stops to allow the gas tank to be pressurized only a few psi of pressure and the sound went away. Anytime the fuel pump stays running with the key on its either a stuck fuel pump relay or most likely a bad engine computer pcm. If the pump runs with the relay removed its not the relay.
















