Fuel gauge problems, anyone experienced the same and fix it?

[Jerry]

Anyone had this and figured out what it was?..........................

 

Gauge works fine: If I disconnect the sender unit the gauge reads full tank (max resistance).

 

Sender units works fine: When disconnected from the loom it shows around zero ohms when resting (empty tank) and 100ohms when lifted to simulate full tank.

But, as soon as I connect the sender unit back into the loom it will not show more than 30ohms when I lift it up.

 

Could this be indicative of a chafed cable mildly earthing out somewhere and therefore reducing the resistance?? any ideas? Could it be the gauge doing funny things?

 

The gauge WAS working fine then one day it just headed south like I turned off the ignition! It came back for two seconds then dropped again and stayed like that ever since.

 

Are there any common areas in the loom on Comanches where the sender cables run that chafe and earth out? Am I even thinking along the right lines!?

 

Appreciate any ideas, thanks guys :cheers:

[jimoshel]

Remove the wire from both the sending unit and the gauge. Then take a resistance reading from it to ground, er,,earth. If that doesn't give any clues then check resistance between the fuel gauge wire and againest other wires in the same loom, fuel pump, tail lights, turn signals etc..You just might wind up doing a inch by inch visual inspection of the entire loom. Might try running a wire direct from sender to gauge, replacing the original.

[Jerry]

Thanks for the advice Jim, I'll give it a shot as you suggested. Your idea of just running a new cable is smart. I'll do the visual inspection and earth, sorry! ground test and if I can't find anything I'll run a new cable :cheers: :thumbsup:

[alex_and_sean]

Let us know if this worked.

[MancheKid86]

how'd it go?

[Sir_Brando]

Hows it coming?

 

I had the same problem and I did as I often do when the electrical gremlins start acting up, and kicked my left foot up and hit the fuse panel/wire nightmare. The gauge popped up to half tank, my wipers started working and my stereo stopped shutting off when i hit the left blinker. Been meaning to fix it but its still working since my last kick.

 

Let us know how it goes!