Fuel sensor

I have a 2002 Yukon XL. the fuel gauge had dropped to empty every time the tank got to half full. GMC indicated the sensor was fouled by fuel residue, and addd a cleaner. No good. fuel garuge crapped again. Sensor was replaced under warrenty, and at 1/4 level, dropped to empty. Would occasionally come back to actual tank reading. Filled the tank, and the gauge came up to 3/4, then would slowly (over about 30 minutes) move to full.

any suggestions as to what is the real problem? Am approaching the end of warrenty and need this problem fixed.

have also experienced battery problems - leave the back gate open for 30 minutes and the battery was dead -- GM says faulty battery, and replaced recently. Seems fuel gauage problems have been occurring at about the same time as leaving back gate open for 15 minutes or longer (maybe my imagination).

A high sulfur content in the fuel degrades the card on the sensor causing erratic gage fluxuations

My 2003 seems to be developing this fuel level reading issue... It will read about 3/8 of a tank or so for a while, then suddenly plummet to E. What's the real deal here? How in the world would a person know if his fuel has "too much" sulfer??????

Our 2000 Yukon XL is having similar problems. After filling, the gauge will plummet to "E" and the "Low Fuel" warning comes on. After a couple of minute it will correct itself, but do it multiple times until the fuel seems to dwindle some. It's now leaving us questioning its accuracy.

Anyone know the fix?

Hi,
the fix is to replace the fuel level sensor.
You have to drop the tank to get at it.
Take care, Eggert :bananasmi

I am having the same problems with my 99 yukon denali

Hi,
the fix is to replace the fuel level sensor.
You have to drop the tank to get at it.

Correct. I talked to the service guy and (for my model) it happens to be a "module"...fuel pump AND sensor. So to replace one, the other is replaced too. Pretty costly.