rjcombs

I have been having some issues with my 96 f150. A couple months back I was driving home when it started acting like it was out of gas. My gauge read almost a half of tank. I would turn the key but couldn’t hear the fuel pump. I banged on the gas tank a couple times and tried it again. Turned the key again and the pump worked and the truck started. It happened one other time after that. Thought it could have been something to do with the ground, so I grounded the tank itself to the frame. That seem to fix the issue until yesterday it started doing the same thing. I tried hitting the fuel tank to get the pump to work but nothing this time. Had it towed home. The next day I go out to see what I could figure out about it and the pump worked just fine and the truck started up. Anyone have any idea what this could be.

raski

Sure does sound like a bad pump,by getting it to work by banging on the tank. Slim chance you could have a bad connection at the top of the tank. I would still measure the fuel pressure. Even though it is working, it will soon fail and won't work again.
Be prepaired to either lower the tank or take the bed off soon.

Steve83

The pump does NOT ground to the tank, so that's doing nothing. Next time the pump doesn't work, have a digital multimeter (DMM) or 12V test light handy, and check voltage from the R/Y wire at the IFS to the green ground bolt; both in the passenger kick panel.

(phone app link)

raski

Unfortunately, that doesn't tell if power is getting all the way back to the pump.

Steve83

No, but it's the most-convenient place to check, without getting under the truck, or digging through 100 wires, so it's a logical FIRST step in diagnosis. It probably won't be the LAST step...