Howdy,

So I've got this truck, its a 1991 F-250 7.5l that runs on gas. It has dual tanks and when I switch it to the fron tank, it sputters like its getting a little sip of fuel, but nothing else. Eventually this will stop and I can't run it all together on the front tank. Could this be fuel pump, clogged lines or something else? Thanks

 

Short answer, yes. It could be the fuel pump, fuel lines from the front tank to the selector valve, or a bad selector valve. The fuel pump in a common cause...

 

I thought Ford changed over the fuel system after 1989. They eliminated the inline pump and selector valve (fuel reservoir) and went to a high pressure pump in each tank.

 

I stand corrected... I was meaning the pump in the front tank, and I thought the gassers had a selector valve like the diesels. The gas trucks have no selector valve. The functions of the selector valve are taken care of with valving in the fuel delivery modules (fuel pump assemblies) in each tank.

Thanks for correcting me!

Back to Jonny G's problem, it really looks like the fuel delivery module in the front tank...
Phy

 

I agree

If there is an open or a short circuit in the fuel pump circuit the PCM will usually store a code. That is why it is important to check for stored (CM) and Key On Engine Off (KOEO) codes before tossing parts at a problem.

 

Have someone turn key on while engine is off and tank switch is on front tank, you should be able to hear if the front pump is working. It will only work for a second until pressure builds but long enough to hear

 

So yesterday, I could hear what I believe to be the front fuel pump working. I would start my truck with the selector on the rear tank. After ignition, I would switch to the front tank and let idle for a while. Then as long as I was on the front tank, I could definitely hear something working. I took it for a drive around the neighborhood, and it seemed to be going fine as long as I was smooth on my acceleration (not hammering the gas). Then took it on the hwy and drove it for 15 miles, no probs. Turn the truck off ran an errand. Actually started up on my front tank (shocked because it has never before since I've owned the truck). Tried to drive it and it started sputtering again.

Since I am pretty green when it comes to Ford trucks, and cars in general, I thought I would share as much information as possible. Thanks guys!

 

Yeah, it still sounds like a weak front fuel pump...