[Nick Spano (74chall)]

Hello, I'm having problems with my gas gauge. It hasnt worked since I have bought the car. Today I grounded it out and the gauge went full. So that means the gauge is ok ( im guessing). The connection between the gas gauge wire and the sending unit is good. I wire brushed it and put some dielectric grease on it. The gas gauge is still buried at Empty, even after I checked the connection. Could this mean a bad sending unit? any suggestions? thanks in advance, NICK

[Douglas Little (Dlittle)]

I just went through the same thing with my Challenger. It sounds as if the sender is not working. Grounding out the wire is good for a check but do it only long enough for a check. On my car I had to pull the tank to remove the unit. The sender was disconnected at one rivet point and there was no connection at the sliding part. It was all reparable. There maybe a chance that your float has sunk. That would be an easier fix. You should check your repare with a meter or the guage before putting it back up.

[Dave-R (Roppa440)]

I guess I was right about that faulty fuel sender when you tried to fill up and spilt fuel all over your toes eh?

I think I have the fault finding instructions for the sender at home someplace. I will look tonight. They are not cheap to replace so lets hope you can find the exact fault and fix it.

[Nick Spano (74chall)]

Thanks guys for your help. I think my float may have sunk,theres a good chance. I want to check out the sending unit to see if its connected. This requires to pull the tank am I correct. I hope the sending unit is not bad, they are expensive , $ 150.00 Us dollars. If you could find the fault finding instructions, It would be a great help. Many thanks, Nick

[Douglas Little (Dlittle)]

I found when trouble shooting my sender that there should be a small resistance even if the float is sunk (wire to the dash disconnect). If the check shows an open circuit the there is something else wrong. You are going to have to pull the sender anyway so I would try to fix what ails it rather than drop that kind of money on a new one.

[Dave-R (Roppa440)]

OK

Here is the full series of tests from the workshop manual. I will cover the lot for the benifit of anyone else wanting to do this in the future.

First check that the earth strap over the rubber hose section of the sender outlet is clean and making good contact.

Next test the gauge in the dash.
To do this remove the lead from the sender and touch it to a good chassis ground with the ignition switched on. Just touch it long enough to see if the needle jumps up. Keeping it shorted to earth will burn the gauge out as it operates on less than 12 volts.

Last of all remove the sending unit from the tank and connect a ohmmeter between the body of the sending unit and the terminal in the center of the unit.

With the float in the 'empty' position you should get a reading of 73 ohms (+/- 12 ohms).

In the full position the reading should be 9.6ohms (+/- 1 ohm).

Hope this helps.

[Nick Spano (74chall)]

dropped the tank today. the float sunk..had a bunch of pin holes so I soddered it up and she works like a beauty. Its very very nice to have a working gas gauge. off to the car show tommrow morning!Thanks Guys