Gas gauge not right

[PJB]

Ive noticed that the gas gauge has been reading more towards full the last few times Ive had the car running (its not driveable yet).
One time it ran out of gas and still showed about 3/8 of a tank. It ran out another time too.
Today I started it and its showing alot more than the 3 gallons that were poured into it the last time it ran out of gas.

I never had a problem with the gauge being off when the car was able to be driven (its been off the road since March). It always worked fine.
Nothing was done with the gas tank, fuel pump, etc.
Ive got a new fuel pump but its not installed yet.

Id hate to run out of gas while driving it once its back on the road because I dont know how much gas is in there.

Is my sending unit bad or is there something else wrong?

 

[aaros]

may be a bad sending unit, i changed mine and it still read wrong for about a month then i started it one day and it has been spot on from then on.

 

[PJB]

Im thinking I probably should change it when I put in the new pump then.

 

[irish]

I'd change it, not hard to replace, mine pulled tricks on me. Guage was always dead, read a quarter tank always, changed cluster to a 140 and had that one tested, all worked, installed it no difference. Changed sending unit, still read a quarter tank. Rechecked all wires, scratched head, scratched head some more. then poured 5 gallons of gas in it, bingo it reads half tank! hehe it really had a quarter tank that last time.....