Pontiac Repair: Grand Am Gas Guage, fuel level sensor, gas gauge

Question
QUESTION: I have a 1999 Grand Am and the gas gauge goes from showing full to empty sporadically when the tank is full.  After filling the tank on way home the gas gauge all of a sudden shows empty and light comes on. What is the most probable cause?

ANSWER: Hey Don:

dependin on the engine in the car it may just need a fuel level sensor in the gast tank. I can;t remeber which engine the 4 or 6 has a different software update for it for better gas gauge responce to go along with the level sensor. You can still have a bad sensor but the software update in the computer. the issue you have is not a software glitch it just improves the operation of the gauge. the senor is the issue here ther wear out over time and a high sulfer content in the fuel is what causes them to go bad. good luck :)


---------- FOLLOW-UP ----------

QUESTION: its a v6.  If I replace the sensor does the tank need to be dropped from the car to get to the sensor? Is it on the top of the tank?

ANSWER: the tank has to be removedout the bottom and the fuel pump module is in the top of the tank. The sensor is sold sepratly from the whole module.


---------- FOLLOW-UP ----------

QUESTION: Sorry to keep bothering you but I have tried to look for the sensor online through the auto parts stores.  I don't see anything but a fuel pressure sensor.  Is that the part or what is it actually called? And thank you for the information you have provided.

Answer
It's called a fuel level sensor. It more then likley is a dealer only part. to tell you the truth any kind of electronic part on any car I would steer away from aftermarket and go with the factory replacemnet part. Not just for GM but any brand use the O.E.M. part only.