Rick964

New to me 80 SC, fuel guage needle sometimes stays put where it should be @ 1/4 tank (I thknk that is where is should be - I'm yet to put gas in the car) but at least half the time it bounces wildly between 1/4 and full repeatedly. I'm thinking this must be a bad connection to the sending unit but is the type of failure you get when the sending unit itself goes bad?

arcsine

Did the car get driven much by the previous owner? I ask as I recently replaced my fuel level sender with a used unit that had been sitting dry for a while. It took a couple of tanks of gas to get the gauge to not be twitchy. My belief is a layer of corrosion may of formed in the sender making the movable part of the sender "sticky". Just took a few swings through the full range of the movement to remove whatever was in the way and now the gauge is rock solid.

rentadate

nice idea. I think I'll do that one with my car.

Rick964

Yes, the previous owner had not driven it much over the last 18 months. Thanks for the idea.

Rick964

Filled it up and it was still bobbing around and never showing full. Took of the sending unit wire connector, cleaned up the contacts and plugged it back in and the guage seems to be steady and pointing to a full tank. I hope that's all it needed.

wholberg

If you continue to have problems, try taking the sender out of the tank, taking it apart and cleaning the wires. My Carrera had a sticking float and I took the sender out of the tank and found a ridiculously small bit of gunk on one of the guide wires that was preventing it from smoothly going up and down. I cleaned the wires carefully and the sender has worked just fine for over a year. SC senders are a little different but can have the same issue.