Fortunately this is an easier fix than in most other GM vehicles like the Chevy Suburban.
In my park ave with the exact same problem, I have a digital computer control center and I just keep an eye on the "fuel used" setting since the DTE number fluctuates depending on whether or not it is in the false "full" position or the actual position. However, if you do not have this same information as in my 2000 model, then you might want to replace the sending unit yourself. Like the suburban (which I have also and it too has a bad sending unit), this is mounted on the fuel pump assembly which is located in the gas tank. Unlike the suburban where you have to drop the tank for access, you can easily access it from within the trunk. (Under the carpet towards the passenger side front). I bought a used one from a wrecked 99 for $65 (the whole assembly) and it took them all of 5 mins to remove the cover and pull it out of the tank. I am pretty sure that the unit is the same for multiple model years and possibly multiple models so you can go to the local pull-n-pay yard once you've done a cross reference and get a used unit cheap.
Note: If it were a relay, you would lose power to the fuel pump and the car would stall or no longer run.
Tuesday, May 18th, 2010 AT 1:45 AM