Illumination of the Check Engine Light can be caused by a loose or worn gas cap.Google+
Car Problem Reports
GMC Canyon Check Engine Light Due to Gas Cap Issue
GMC Canyon Problem
Average Mileage: 87,700 mi (28,000 mi - 160,000 mi)
check engine light on
Visitor, 2006 GMC Canyon, 28,000 mi
check engine light comes on after a few miles of driving
Visitor, 2005 GMC Canyon, 118,000 mi
My engine light comes on and my engine idles rough, but as soon as the light goes off (randomly) the engine runs fine. The gas cap light comes on my dashboard warning me the it is not secured, I twist of the cap and put it back on, sometimes this will trigger the warning to go off and everthing is fine. That would be wonderful it that was all it was. I am replacing my plugs, air filter and fuel filter to see if these contribute to the light being on.
Visitor, 2005 GMC Canyon, 70,000 mi
rough idle and engine would die...new gas cap and problem was fixed.
Visitor, 2005 GMC Canyon, 160,000 mi
I am buying my 4th gas cap. original lasted ~95k, two after market failed during next 60k.
Check engine light...
..turned off after replacing gas cap..
... came on again.. months later.. not fixed with another gas cap..
Check engine light is on again.. Going to have diagnosis done.. but Terrified of being 'sucked into' the nightmare
of "single woman.. unknown problem" .. gotcha.. with Mechanics..!!!
Mass air flow sensor? OMG.. not the catalytic converter!!
Visitor, 2006 GMC Canyon, 90,000 mi
I have the same problem with the gas cap