Ccporter

I would check your tank selector solinoid, I had an old 3/4 gmc w/ dual tanks same exact problem, it was a bad selector switch

Ccporter

Also if you have had any return lines off make sure they are feeding back into the correct tank , my dad had that problem with his 95 f150, it would actually over flow the front tank when set to run off the back tank

corndogia156

It wouldn't hurt to blow into the fuel line from the pump and listen for a leak. If the hole is small enough you could be sucking air without leaking gas. I had this problem with my rear tank.

GhostriderI

And it is "fun" to find, I had that happen on an old car but I was getting fuel to the carb. and the car would idle but would not get above 25 mph with your foot to the floor (I was 21 and thought I knew it all ) My father ask what the problem was I said fuel pump he took me to the parts store, I bought the pump, installed it, did not fix the problem, My next part was the carb., same deal, did not fix the problem, he then told me to check the rubber line on the sending unit I found a "small" pin hole and under load it would suck air along with fuel... .50 of rubber fixed the problem.. boy did I feel dumb... Then I realized why he kept asking if I was sure if that is what was wrong. I think he knew all along but wanted me to figure it out. expensive lesson I have never forgotten. I miss my old Blue 1967 Pontiac Tempest 4DR 235 6cyl 1bbl OH cam power glide

GhostriderI

Bump any updates

louderr57

I have almost the same problem well sort of. I have an 85 f 150 lariat with 2 tanks I replaced the front tank and inner tank pump, I have the switch to the front tank. I know the back tank is empty and the pump is shot, the truck has been sitting about 6 years, It runs with a shot of ether but isn't getting any gas up to the motor, I put 5 gal in the front tank. I do not hear the pump run when I teurn the key on so I don't know where to start???

GhostriderI

I'm guessing you have a 302 (5.0) EFI is that correct?

louderr57

Yes 5.0 efi. I think I found the problem. The canister fuel filter has a small pressure thingy up inside the filter assembly thats bolted to the frame. Well it was blocked solid. So I had to go to the junk yard and pull another one off a truck there. It should start getting fuel to the motor as soon as I reinstall to my ford.

1967 Tempest

Was that the issue?

stevebuchta

Turned out being a small air leak in the fuel line. Small enough to not cause a fuel leak but to allow air in the system. A giant pain in the *** to find but replaced the fuel line and haven't had a problem since.