Check gas cap
 

DIC told me to check gas cap, looked fine, then Check Engine Light. What to check next? Do I need an ODB meter to pull codes?

If the gas cap was not on tight, you will get the code. After you re-tighten it it will take a while to re-set itself, or you can get somebody with an OBD scanner to clear it, or go the disconnect battery route. Just did this on the OL's Mazda yesterday, on the '99 Mazda the code said "leak detected in" whatever they call the fuel vapor recovery system. Anyway, just relax after you turn the cap to 2 clicks give it some start/stop cycles. I notice you are in NJ which means an attendant, not you does the fueling.!!! QED

Low voltage at the fuel tank pressure sensor will indicate the same code if the cap doesn't solve the problem. I believe the trouble code is PO452 or PO453. Not sure about the HHR, but in other Chevys it's about $30-$40 for the sensor.

My mechanic suggested giving the gas cap a few extra turns after filling up. Very rarely has the engine warning light come on since starting to give the extra rotations.

However the engine light does come on sporadically and then goes off on its own. Most times by restarting the car means the engine light doesn't come back on. There is oil, fluid levels and good with no variance in operating temperature so I ignore the warning.

My mechanic said dropping the gas tank was one of the first usual steps recommended to find the problem. He didn't recommend the expense to find a problem that just turned on a warning light.

2006 hhr 160,000 ks.

My car did the same thing the dic. read "check gas cap" it happen one time it did not set a code and has never happen again. that was two years ago.:clueless: last winter I did have a code for an evap. leak and I had to replace the vent valve. maybe it was a early indicator.

I recently experienced the same issue... However it was not the gas cap itself... There is a piece located above the rear axle that has to do with the evap recovery system or at least it appears to... this piece was totally busted and hanging by a hose... did a temp fix until I can replace it and the problem went away..... I would inspect that piece if I were you... I would post a pic but am out of town til tomorrow or fri...

That is probably the evap charcoal canister. Believe it, or not; they expect you to change that thing occasionally, I don't remember how often, but it's like the radiator hoses......:propeller::corny::roflol:

check gas cap
 

I know this is an old thread but I just had the
CHECK GAS CAP message come up on my car stayed on for a couple minutes then went out.
Came out of a store an hour later still no message drove about 5 miles message came back on for a minute then went on gas cap and filler neck appear to be fine and no check engine light any ideas ?
Seems to be one of those weekends just put in a thermostat in my wife's suv with a chevy 3.4 l those are always fun
Any ideas on the check gas cap would be great

Check your gas cap itself, I had some "fun" chasing this issue with our '06 and it turned out to be a bad cap.

The rubber o-ring/gasket on the cap had cracked breaking the seal and it made the vehicle "think" the cap was loose or missing.

Being that you have an '07, that cap has been on and off quite a few times, so that's where I'd look first...they do wear out.

When my wife and I went to Tennessee last October I drove from where I gassed up south of Indianapolis to Cleveland Tennessee, with the gas cap hanging out the gas fill door.

No lights came on telling me anything. The car drove with no performance problems at all.

Makes me think there is a sensor problem of some kind, but I’m not to worried about it.