Got a 2002 F-350 V-10. Just bought the truck a few months ago. It ran great and it started acting up. Driving down the road and just shuts off. You could stop turn key for a minute. Crack it over and fired right up. Might not do it again. But then sometimes do it few miles down the road. Last week it completely quit. Had no fuel. I changed the fuel filter and fired right up. Drove it probably 20 miles that night with no problems. Wife went to start it to go to work the next morning and it wouldn’t start. Checked out and changed fuel pump. Same thing started right up drove it that night probably 30 miles with probably and once again next morning wife went to sart it and no go. Got my butt chewed.
I got to checking for power. Crash switch power in and out With the pump plu unplugged I get 12 volt for 2 to 3 seconds then less power after. Got another power I’m assuming for the gauge. When you plug the pump up you don’t hear the pump running and check power there is no power. The plug looked like the ground prong wasn’t making contact so I separated the wires from the plug and hooked them direct to fuel pump plug. I am getting power to pump and gauge wires until I hook the ground wire up then no power. I thought maybe the new pump took a dump so got another one but before I dropped the tank again I hooked it up. And same thing. Have power until hooking up the ground. I run a power wire from battery to pump and held it on there a few seconds and you could hear the pump With wires unhooked to plug but knew pump had pressured up I cracked it and fired right up till ran fuel out of line. Not sure why I’m losing power when plugging in the ground. Any ideas?

 

Just run another ground is

 

I would cut the ground wire to pump abt 6 inches from pump, then tie into it with same gauge wire and run it to a good body or frame ground

 

i tried that and it still cuts the power to the pump

 

Well, I'm not too good on all this electrical stuff but if I'm not mistaken the ground for the fuel pump is controlled by the PCM, so you're more than likely going to have to trace back to the ground pin on the main harness or there may be a problem with the PCM or a relay switch itself.

 

It's not a ground problem, it's a power supply problem that fails under load.

Sounds more like the fuel pump relay, which, unfortunately is soldered into the fusebox, is failing. A not uncommon failure for the models stating in 2002 and for a couple of years.

Instructions to verify diagnosis and to repair have been posted multiple times.

 

He ran a power wire directly from the battery to the pump and it still lost power. Bypassing the fuel pump relay with direct power from the battery would not cause it to lose the power, Unless he tapped into a line for the pump in the engine compartment instead of applying power directly to the pump.

 

That is not what he reported. Go back and re-read his post in total.

 

thank you I’ll give it a try

 

I ran power wire from battery to the fuel pump and then grounded to the frame and the pump kicked on