Gas gauge not working?

The fuel gauge sending units are problematic in GM's from the early 2000's. That unit is a part of the fuel pump assembly, which is in the fuel tank. Honestly, if it were my car, I would just keep it above a quarter tank. Those pumps can be pricey to buy and a thorough pain to replace.

The gas gauge on the meter is swinging back and forth from empty to full and back. What could be causing this problem? and how can I fix it?

Mark Smith

The Fuel Level Sensors GM used in these (and several other GM products) did not like the sulfur content in gasoline. The result is fuel level sensor contacts/grid corrode away.

A new sensor is around 70-90 dollars. Sometimes these can be found new for under 30 dollars on ebay. Beware if you don't get the right one you'll need to melt and resolder the wires (using your old connector). Easy to do if you have any experience.

The fuel level sensor is part of the fuel pump assembley. The good news is you do not have to remove the tank. Instead there is an access panel in the trunk. Still dangerous opening up a gas tank... reply back for further instruction if this is a job you wish to tackle yourself.

Should be a recall on this, but has not been.

when the tank is full shows full.when the tank is one forth shows three fourths and thats about low as it goes what could be wrong?

Chances are the rheostat on the float is bad. THat is basically a resister that sends different amounts of power to the Body Control Module based on how much fuel is in the tank. The lower the fuel level, the more resistance and the less power is sent which inturn should lower the gauge.

One bad parts about this. This is part of the fuel pump and is located in the fuel tank. Not a fun or cheap job.

I own a 1997 Buick LeSabre. I live in Iowa. We drove it to California. While in the mountains of Colorado the gas gauge quit working. This was 2 yrs. ago. It still does not work. I just watch my mileage and gallons but does get a little tricky sometimes because the mileage changes. So, consequently we have run out of gas a few times. Also, when the gas gets low the car will stall on turns. I fill it up and sometimes there is still as much as 1/4 tank of gas yet it acts like it's empty. I was told it would be quite a job and like $150 bucks to fix it so I have just kept track of things.

Hi It sounds to me like you need a sending unit. which in terms means a fuel pump. does your check engine light come on? It might even be a bad fuse so check your fuse box... hope this helps you.. :D

No, my check engine light is not on. Just today again, I thought I had enough gas (judging by the gallons/mpg), however, it died twice on corners and I barely rolled into a gas station. It then took 19 gallons. Which I realize is pretty low. But, it seems that whenever this car is even near low it just can't keep going. Thanks for the reply.

By the way, what is a sending unit? Would I need that plus a fuel pump? Would this be major labor involving taking off the gas tank?

yep the fuel pump is in the tank on that model. there is something called the float in the tank that measures how much fuel is left and i believe it's mounted to the fuel pump. i recently replaced my fuel pump on a 1991 buick century and they charged me $700.00.

Well, I am going to try this again. I replied but I don't think it posted, if so then sorry.
Your description sounds like that is what is wrong with my car. However, for that price I believe I will just watch the miles and gallons and make sure I always fill the tank frequently. Thanks.

I'm glad i could help you out! Good Luck! :D