Why would all my gauges work, but not the gas gauge?

Question

I have a 2004 Chevrolet Cavalier which I purchased used last month. About 2 weeks after having it, I accidentally double-started it and that's when it happened. However, now sometimes it works and most of the time it doesn't. I know when it is working by simple mathematics of my mileage usage. Any ideas? Some say they'll have to drop the tank while others say it may be a loose wire . .

Answer 1

you need to have a shop check this becaue it may not be the sending unit bad in it,so you may not have to drop the tank ,if it started when you did that it could be a connection bad on it a good repair shop can check it for you and tell you if its the sending unit bad or the gage its self, that might be burnt out,either way having someone check it may save you some money ,good luck.

Answer 2

Depends on how the tank arrangement is on that model some cars you can access the full sender through the boot but most of the time the tank will have to be dropped..(The fuel sender is basically a float switch which varies the resistance in the wiring circuit)...Also check the connections on the back of the gauge sometimes they come loose there..(look there first before taking any expensive options...  

Answer 3

GM (Chevy, Pontiac...) has had an ongoing issue with the sending units in their vehicles.  I've heard several explanations for this but the most common and sensible is that some of the fuel additives in today's gasoline corrode the rheostat area of the sensor and they stop working.  You will probably have to have the tank dropped and a whole new sending unit (pump, sensor and frame) installed.  If you do have to do this and you intend to keep the car, get a lifetime warranty part at a garage which can be reimbursed for the labor by the parts store if it goes bad again.  NAPA Auto Care Centers offer this type of warranty.  Your double start was an unfortunate coincidence because there is no connection between the two systems.  It could be a bad or loose wire (they will not know until they drop the tank) but I wouldn't bet on it.  Sorry.

Answer 4

you could have a short in a wire to the sending unit but most likely its the sending unit

Answer 5

Could be a loose wire, could be the sender in the tank, could be something else... only way to tell is to test it from the gauge backwards.