Gmc Envoy with erratic fuel gauge.

check connectors fuses and relays ----also check the connections ribbon connections and unit under rear seat drivers side --lift seat like your going to fold down

bad cluster..

The fuel level sensor is in the gas tank, and if it needs to be replaced, the tank must be removed from the truck.
Does your gas gauge work correctly? If not, there could be a bad connection at the tank/sensor or the sensor itself is defective.

Although my first impluse is to tell you to do is to drop the tank and check the fuel pump and level. All GMs have had a terrible record with their instrument panels for 2002-2006, so think back and try to remember if you have any other malfunctions with the instrument cluster. If you have, then I would look on the internet and find the places that have made a specialty of rebuilding GMs instrument clusters and have them rebuild it completely.

{: ) It is still safe to drive as long as you are aware you have enough gas for the trip. The problem is your fuel level sensor could be getting erratic and sending inaccurate signals to the engine control module, thus illuminating the check engine light at times. If you unexpectedly run out of fuel, thats when you will stall on the road. Better have it checked as soon as possible.

it needs a new float. it will be available to you at your local GM dealer. u need to remove the tank and fuel pump assembly. replace the gauge float and reinstall

Common problem on the 03-06 Envoy instrument clusters for the fuel gauge to go out. It's usually caused by one of two main problems, either the stepper motor on the cluster's circuit board is going out or the sending unit on the fuel pump is going out. Check out this blog post about the problem - Envoy fuel gauge problems

Suspect faulty fuel sender. Fuel sender is attached to fuel pump in tank.

Is it ALL of the gauges? My wife's 2005 Envoy Denali had a problem with the gas gauge sending unit (in the tank) that made the gauge act erratic. Also, the check engine light would stay on alot. If it is all the gauges, then it may well be the dash unit. Hope that helps some.

I just had the same problem and the dealer told me that it was an erratic gas gauge. They needed to fix it.