1999 ranger fuel guage

[dangeranger]

my fuel guage is stuck above full all the time and its finally gotten to the point where i need to fix it......

ive installed a new ford sending unit and still, it reads full...

ive moved the guage needle to empty and then turned the key on and it rises back to full...

does this mean that one of my sending unit wires is grounding out somewhere?? the haynes manual says to remove the tank connector and ground out the wire that has no battery voltage, and the needle shoudl drop to empty. but ive done this and there are three terminals with no voltage then some read 12 volts and some read 5-7 on the 8 pin connector on the tank.

how do i go about locating this problem and which wires should i test with my multimeter?

the truck is a 99 3.0 flex fuel regular cab if that helps

joel

 

[dangeranger]

bump

 

[knux511]

i've got the same problem with my 98

 

[Earl43P]

Always reading Full means you have an open wire, probably the YE/WH to the fuel tank.

Could also be the BK/OG wire that provides the ground from the fuel tank sender (it needs to be ground).

If you ground the YE/WH wire momentarily, the fuel gage should drop to Empty. Don't hold it to ground very long, because the Empty signal is really 22 ohms (Full=145 ohms). A long duration short to ground may blow the fuse, so have somone watch the gage while you do it to keep the duration very short.

Concentrate your efforts on the entire length of that YE/WH wire. It stays that YE/WH color all the way from the tank to the instrument cluster.

Hope that helps.

 

[wvcat]

I had the same problem. I discovered the harness wasn't plugged in all the way under the truck near the rear of the transmission. There is anothe plug on the same hasness but its up behind the dash and has a bolt in it to hold it together.
John