my fuel pump works but gas gage wont should i pull tankor not

 

[quote=al wetzel;60477]my fuel pump works but gas gage wont should i pull tankor not or is this a bad fuel gage

 

Welcome to the forum. Umm some truck info would be helpful, but it could just be a wire somewhere that got corroded, or unplugged.

 

I have a 1987 F150. 6 cylinder with dual tanks..... the gage doesn't work on either tank. On the front tank, the gage goes way past full..... on the rear tank, the gage goes way past empty. I am using the method of driving 200 miles then switching tanks.

Any suggestions would be appreciated.

Gasseous

 

these particular F150's were notorious for the dual tank setup going wrong.

I'm with drakebuster - check out the wiring and the relays for a fault.

We know there getting power because you mentioned there both working, just not correctly. I'm wondering though, what are those lever things on the fuel pumps themselves that move up and down with the fuel level? I'm wondering if the both the fuel pumps have those things corroded? am I making sense here?

 

We know there getting power because you mentioned there both working, just not correctly. I'm wondering though, what are those lever things on the fuel pumps themselves that move up and down with the fuel level? I'm wondering if the both the fuel pumps have those things corroded? am I making sense here?[/quote]


The lever things you are talking about are the fuel sender units, they tell the truck how much gas is in the tanks.

I'm wondering if the gauge problem started right after changing your fuel pump because otherwise it would be unlikely to have those units both get damaged and in opposite directions. I would check the wiring and relays first.

 

thank you mathteacherrob! been a long day for me lol! I felt like an idiot just describing it the way I did LOL! NBD

 

The sending units go bad on these years all the time. Mine also don't work correctly. Changing the sending units will require changing the pick ups but you can reuse the pumps.

 

I inherited this truck from my Father. To my knowledge, the pumps are original, as are the sending units. I have other electrical problems, such as the right turn signal light shows on, on the dash, but it isn't. (This only shows when the headlights are on). The radio speakers come and go at will. The alternator light flashes. That sort of stuff. I have driven over 2,000 miles with these conditions, so I know that they are false indicators.

I will check the relays first. Any hint on which one to look at and where is it located?

Thanks,

Gasseous

 

Sounds to me like you have a few grounds that may be bad. Either broken wires or corrosion where they connect to the body. Finding these bad grounds will be a PITA most of the time. But then again once you find the problems you have a very solid truck on your hands. Sounds to me like you have a project that will occupy those idle hours you may have on your hands. Good luck