Guys,

I have an 06 Trailblazer EXT. Need help with an idiot light that keeps coming on.

A while back, I ran out of gas, called OnStar and they sent someone with a gallon of gas. The guy put the gas in and we started down the road again. Almost instantly, the check engine light came on. I checked the manual and it talks about some kind of emmissions issue. When I got to the next gas station, I noticed that the silver "flap" inside the gas filler neck was missing.

Does anyone know what this "flap" is for? The dealer has replaced the O2 sensor(s) several times and can't find the issue. I'm out of warranty now and the light came on again today. It seems to come on more often when it's cool outside. When it's really hot (like it has been in Indiana for the past month), it never comes on.

Any help is appreciated!!

 

Anybody??

 

i don't know, but i have recently acquired an 04 Trailblazer, my check engine light came on and the owner's manual says to replace gas cap and let it reset. i tried that and noticed te cap doesn't fit properly at all. i'm not sure this is even the problem. but wondered if anyone else knows

 

The owner's manual suggests that the Gas Cap MIGHT be the problem when a check Engine light comes on. What you really need to do is have the Code read so that you can learn more precisely what system is brining up the Check Engine light.

 

thank you. i had it read at AutoZone. there are 3 codes-but he said the one that concerned him most was P1680, it doesn't recognize the Vin# so he said that they had apparently installed or worked on computer and not transferred everything. what next?

 

p1680 is an accelerator pedal position code but it could also be related to a failure in the Engine Control Module (ECM). There's supposedly a Technical Service Bulletin that might help but I could not find a link to it. I'd suggest it's time for a dealer to look at your Trailblazer.