Gas gauge quit working?

[TStone 10]

My gas gauge was working fine until I unplugged the wire from the tank sending unit and plugged it back in - now when you turn the key on it goes past full and stays there??? Any ideas?

[buening 63]

It is grounding out somewhere. If you touch any sender wire to the body, the gauge will peg. Maybe you pushed the wire on too far or its touching something.

[TStone 10]

I took the wire back off and reseated it but I did push it back on fully - So aare you saying to try backing it off just a bit?

[buening 63]

yep and try squeezing the plug slightly to give it a tighter grip. Just be careful not to completely crush the plug

[mymach 0]

Does the gauge drop back down when you disconnect the wire at the sender? If so, it's a short to ground in the sender itself. The post of the sender that the wire connects to should be insulated from ground so I wouldn't think that pushing the wire on "too far" would be the problem. If the depth of the connector on the post does cause the gauge to peg, that in itself indicates a problem with the sender (short to ground at the connector post).

 

If the gauge doesn't drop back down when the wire is disconnected, the sender wire is grounded somewhere upstream towards the gauge.

[TStone 10]

Does the gauge drop back down when you disconnect the wire at the sender?

 

Yes

[mymach 0]

Then, for whatever reason, the connector on the sending unit has continuity to ground. It could be a failed resistor in the sender, possibly a failed insulator where the connector is attached to the flange of the sender. There are any number of possibilities, but it sounds like it's time to pull the sender out of the tank and at least check it, preferably with an ohm-meter.

 

Just my two cents....let us know what you find out.

[TStone 10]

It just kills me that it worked fine until I unplugged it - I tried backing it off a bit - no change

[mymach 0]

In 30 years of wrenchin' for a living I've seen lots of "weird" things happen with electrical systems/devices. Any number of things could have happened. Maybe the insulator on the connector was deteriorated and pulling the wire off was just enough to disturb it and allow the connector to contact ground, or something oddball like that. Yeah, it can be hard to accept at times, but "Murphy's Law" has never been repealed....lol

[TStone 10]

It started working on it's own last night - ghosts in the machine

[Pakrat 1,043]

Well that's lucky but don't be surprise of the next bump in the road kicks it back off. :001_rolleyes: