Question for GMC Canyon/Chevy Colorado owners

Question

I have a 2008 Canyon SLE with the 2WD with the 5cyl. My truck seems to have louder than normal engine noise when accelerating. Also when at idle....if you rev the vehicle, as it is coming down, there is some noise in the exhaust that sounds like a mini misfire, tail pipe is BLACK. No check engine lite and no codes apparently. Had it in, the service dept thought it was a problem with the exhaust and went and pulled a new one off their lot to swap exhaust systems....

The new truck was doing the same thing. Left the service folks scratching their head. He checked the bullitens and nothing was on the board. Unfortunately with no check engine light and no codes AND a new truck doing the exact same thing, they have nothing to go on.

The backfire is quiet, you literally have to stand behind it to hear it...you can open the door and it sounds like a "clunk" as it decelerates.

Any other Canyon/Colorado owners experience this? If so, did you get it resolved? WHat was done?

Please advise. Thanks

Answer 1

Does it have a resonator in the exhaust system? They kind of look like a small glass pack muffler, and are located towards the end of the system rearward from the muffler. Sometimes they can cause a sound like you describe. If this is the case there may not be anything that can be done about it until GM comes up with a solution.