Replaced with new K&M
I replaced an stock air filter with a K&N and last evening when driving it started to misfire, check engine light came on and off I could hear the blow off valve and loss of power. Any suggestions. I just purchased in July with 22K on it.

 

Pull the codes for the Check Engine Light and see what it points to. Post up those codes here if you need help decoding them. Codes only though. We don't deal with descriptions of codes because many of those can be misleading.
Did you see my other post regarding using the K&N filter ? Just wondering if that could be an issue.
Also check to make sure the MAF wiring is plugged in securely. If you had it unplugged, you wouldn't be the 1st one to forget to plug it back up.

FYI. Our little cars don't have a blow off valve. They have a bypass valve on the turbo itself.

 

And since you have the GMTU you need to look at the junction of the added on wiring harness; if it is crimped you need to solder it up. And check the TMAP for banging into the A/C.

That is not even getting into how much rodents love to eat wire insulation.

 

Thanks so much! I'm going to check and will post an up date later.

Yes I did read your post.

 

By the way if that's your HHR pictured it is one Sexy Machine!

 

Thanks a lot Sir! I'll check and post later!