The gas tank has a lose connector that leaks and allows fumes to escape. *tr
We have had numerous electrical problems with the envoy, but i am writing about the instrument cluster panel. the failure of the panel caused the speedometer to fail. the speedometer registers over 120 mph regardless of the speed of the vehicle, or whether the vehicle is turned off or on. the mechanic who investigated the issue stated that there were numerous diagnostic errors that had to be corrected before he could successfully diagnose the bad instrument cluster. this is a known issue with the envoy, gmc will not accept responsibility and the failed instrument panel can result in accidents.
Dash gauges/ first the oil level gauge died, then the speedometer started acting up, it will say your going 200 mph, when your standing still...then the speakers and the radio started acting up, work, don't work...really concerned about speedometer, and if other gauges will follow suit. *tr