Check Gas cap
I've got an 06 G6 GT with almost 120k miles on it. "Check Gas Cap" started a few months ago. I finally bought a new gas cap at Auto Zone and I thought I fixed the problem. My husband started driving it and said he never saw the warning again. But of course, the first time I drive it after the new gas cap, it dings and shows "Check Gas Cap" again... and... drum roll... Then I got the dreaded check engine light! Checked the code on that at home and it was PO455.
I took it in. It's been at AAMCO since Monday. They said it was throwing 4 codes. They are charging me $400 to run diagnostics on all four codes. It's now Friday and I still don't know what is wrong with it. I think my AAMCO is under new management and they are probably screwing me. The only reason I took it there is because I had a similar issue with a different automobile about two months ago, and they had awesome service and went out of their way to help me and to not screw me. So, I am probably very, very screwed right now.
I have done every scheduled maintenance on this car (and then some). Besides putting four or five sets of rotors and 6-8 sets of brakes on this thing, and constantly having to get it aligned and balanced, I really haven't had any "system" trouble with it. It got new spark plugs and lots of new goodies, and it recently passed its smog check.
So... This sucks, and it's quite surprising, since it got a clean bill of health on it only a few months ago.
Anyway, I'll let you all know what they find.