About 6 months ago I posted on here about my 99 sd w/5.4 had died and wouldn't start. No fuel. So I ended up dropping the tank and replacing the fuel pump. I installed a USA made Walbro fuel pump so I wouldn't have to do this again. That seemed to fix it, it's been running fine. Well, it just died again........same exact symptoms, same result. No fuel. Can someone explain why this is happening?
I have checked all of the fuses, changed the fuel pump relay.....is there any way to test the pump without dropping the tank? I'm thinking this might be an electrical problem?
The tank was super clean last time and the filter was changed then too. I am careful to keep at least 1/4 tank of gas in it. I am grateful for any help you guys can give me....thanks

 

I worked at a shop and there was a period of time when it seemed like all we did was replace fuel pumps. On one truck however it returned not long after the pump was replaced with the same issue. turned out that the wire harness connector was just corroded. When we dropped the tank to replace the fuel pump, just us un-plugging and re-plugging in the connector gave it a good connection. But a few days later the connector crapped out again and back it came.

I'm sure there is a resistance test for it. I dont know the specs for it though. Maybe contact Malbro? But did you check that power is actually making it back to the pump itself?


Dan

 

I was thinking the same thing....maybe unplugging and replugging is what made it work last time. On a hunch, I found the old pump and hooked up some jumper wires....it spins! Will test further to see if it actually pumps fuel. Will probably have to drop the tank to check connections unless someone has any more ideas?

 

Hope it all works out and the electrical gremlins dont have you pulling your hair out. good luck. That truck that I was referring to was a box truck thrown on a GM chassis, so the connector was kinda just in an odd and exposed spot. We should have suspected it right away but it was a lessoned learned.

 

All the shops I know of this way refuse to put in an aftermarket pump, cause the failure rate is high. They always go oem ford.

 

Ok, got it running.....I fiddled with the plug, reconnected it a few times. Definately a wiring problem all along. I am going to try to pull the entire harness and check it for problems. Thanks for your help!

 

Be sure to check the ground. Should be one on that harness to the frame, not too far from the connector.

 

no problem, glad it was a simple fix this time.