Service technicians have checked repeatedly and find nothing wrong.
GMC Q&AAsk Your Question
2002 GMC Sierra 1500 Question: Service engine light is on most of the time. Tech finds nothing wrong.
Answer #1Greg's Orange Auto (15380 Answers) , Orange, CA - (714) 361-9386globalhelper October 30, 2012, 15:37Master
if the light is on there has to be a code.poss need a better scanner.some of the smaller scanners can't read all data
Answer #2BLSessoms October 30, 2012, 16:36Rookie
My car was doing this--turned out, it was the gas cap not seating well--cap was not turned enough times to tighten. (You may have to turn off ignition/turn on/turn off a few times for the light to go off if the cap is the issue).