DMCC

I need help! the fuel pumps will not turn on. Prior to not running at all, I could be going down the road and the truck would act like it was out of gas. it might start back up immediately or it might not. Replaced HP pump and one of two tank pumps. It would still do this intermittently. Now it does not run at all. Replaced the relay by the air box, no help. Tank switch tested OK. What recommendations does anyone have.

Dead 150

FingOldRebuiltDodge

Check the connections on the pump on the frame. Most of the older ones used 2 pumps. One in the tank, one on the frame on the driver's side. They had problems with bad connections at that one.

Jim

darrengj

I had a similar problem with my 86. I replaced the fuel pumps and relays first with no luck. It ended up being the TPS sensor. I replaced it and the truck ran great. No more stalls, no more studder.

Darren

kadabraz

i am having a similar problem with my 89 f150. except the back tank works fine and the front tank is the only one acting funny. the front tank has issues like the bogging down and studderin then when i swift to the back tank it goes back to working. also the front tank wont hardly let me put gas into it. yesterday i tried to put the change from my gas that the back tank wouldnt hold and it only let me put in .87 cents then it spit out what i would think is more than .87 cents worth of gas back out at me. also the front take fuel gauge reads overfull all the time like its grounded out or something. im not very mechanically inclined so i have taken anything apart of checked any connections or anything. do you guys know what might be causing these problems?

Fast Hampster

Welcome to the forum! Overfull gauge readings are probably caused by sending unit failure. If you're about to repair this issue, you'll need to drop off your tank, and that would give you an opportunity to fix that "i will not drink it" thing. I'm guessing that front tank filling pipe is clogged up or installed incorrectly. it's pretty hard to remove it without removing tank or bed.

Just call me Sean

iTrader: (1)

It sounds like the front tank pump isn't working. You have three fuel pumps, one in each tank and one on the frame. Since the rear tank works then you know the frame mounted pump works fine, since each tank shares that pump. Since the front tank isn't working then it may be full, which is why you can't put gas in it. Although it's possible for these trucks to cross fill the tanks, it's not as likely on the '87-'89 trucks since they have a different type of selector valve. You need to see if the tank is full, because on mine the front tank doesn't like to take gas as easily as the rear. I have to pump slowly for the front or it comes rushing out.

alaskafunboy

Check the 'rollover' switch, some times referred to as the inertia switch. It is located inside the truck on the firewall about half way up behind the clutch pedal. there is a reset button that pops up, i can't remember if the button is red or white, but the it pops out of a black box. push it down to reset it. The purpose of the switch is to prevent the fuel pumps from runnuing dry for too long. When it senses the change in current, it trips like a circuit breaker. This happened to me when I was on a boat ramp. I had very low fuel, and when I went down the incline of the ramp to unload my boat, it ran dry and died. I ended up jumping power to the fuel pump to get up the ramp. Believe it or not, I found out about the inertia switch in the owners manual. Good luck

bitterpill

Can anyne assist me with an 87 fuel pump issue?