One problem related to adaptive equipment has been reported for the 2005 GMC Envoy. The most recently reported issues are listed below.
Same problem everybody else is having with there Envoys, floating fuel needle, now my check engine light is on which occasionally will go off, but now I can't pass emission inspection because my check engine happens to be on, and now I am forced to get the problem fixed in order to pass inspection. Thanks gm, just what I need a week before christmas. Only 60,00 miles on car and I have to deal with this. Could possibly be last gm car bought in this house.