A Loose or worn gas cap may cause Check Engine Light to illuminate.Google+
Car Problem Reports
Chevrolet HHR Check Engine Light Due to Gas Cap Issue
Chevrolet HHR Problem
Average Mileage: 81,525 mi (48,500 mi - 180,000 mi)
Visitor, 2006 Chevrolet HHR, 72,354 mi
check engine light comes on for a couple days then goes out for a couple days
i have change out the camshaft sensor and still my engine like still come on, where is the crankshaft sensor located on my engine....please help me....i check my gas cap and make sure it is on tight.
Visitor, 2006 Chevrolet HHR, 80,000 mi
Replaced gas cap stayed off for 1 week then came back on.
I have a engine on and they are taking about a new engine
Visitor, 2008 Chevrolet HHR, 48,650 mi
Same issue - replaced gas cap and all is still well at 52418
Visitor, 2011 Chevrolet HHR
Check engine light is on just looking for similar problems oil is good!
Visitor, 2008 Chevrolet HHR, 81,880 mi
Gas cap gets loose and check engine light stays on
Visitor, 2006 Chevrolet HHR
Twice this problem happened to me. Replaced the gas cap and it worked for a few years. Now its doing it again.
Visitor, 2007 Chevrolet HHR, 65,000 mi
Engine light came on - checked gasoline tank cap - blew it off to clean - replaced it and light went off - has periodically come on again and then goes off again - some brands of gasoline also seem to cause it to come on -
Visitor, 2009 Chevrolet HHR, 48,500 mi
2009 HHR. At 48500 miles, the check engine light is on. I changed the spark plugs and coil caps. Light stayed out for few hundred miles but now back on.