i've just noticed some engine noise , and the engine is vibrating too much , so much that sometimes even comes thru the steering wheel and you can see the exhaust pipe jumping.....under the hood it moves back and forth about 2 inches...i have noticed no difference in performance or mpg....could it just be the motor mounts are shot ?.......also i checked the brakes....i was amazed to find alot of pad left on the outsides of the rotors , but on the inside of both rotors , the pads are down to the metal.

 

They have a 100,000 mile drivetrain warranty, I would take it in and let the dealer take care of it under warranty. I am not thinking the engine should be moving around.

 

It could be any number of things, including a mis-fire somewhere making the engine shake. The folks are right, take her in before the 100k warrantee runs out. Best of luck with it. Marc

 

Not to rain on the 100k warranty parade, but unless the problem is caused by an internal mechanical issue with the engine itself, it won't be covered. A motor mount is not an internal, moving mechanical part. If its a misfire, it needs plugs or something else. In either case, those are maintenance items, not mechanical defects. At a minimum, change the plugs and O2 sensors. You may also want to clean the throttle body and run a couple of bottles of fuel injector cleaner through the next two tank fulls of gas.

I just did all this to my Trailblazer that has 110k. Its unbelievable how much better it runs now.

 

the plugs were my 1st thought...but like i stated , i have seen no difference in performance or mpg.....i regularly put infector cleaner in , twice between oil changes , and if use seafoam i do see a difference in mpg...i never seen a 02 sensor cause a vibration , but there are a lot of things i've never seen...i hope i get a chance to take it to a dealer.....they will check for warantee issues with no charge ? i have no intention of paying...i very rarely do , as i do most all of my own mechanic work.

 

Sorry. I didn't mean to imply that the O2 sensors might cause vibration. Its just that they aren't good for more than 100k anyway, so if you're changing plugs, change the sensors too.

 

I would think a bad O2 sensor would throw a code.

 

I would bet it's motor mounts since it's not throwing a code. The check engine light would be on and/or flashing if you had a misfire. And if I remember right you have an 06. It does not have the 100K powertrain warranty.

 

I reason I mentioned the 100,000 mile warranty is the HHR is listed as an '08 in the profile. I just assumed it had the warranty

 

It is. My bad. Did you look at the thread from ChevyMgr about what is covered? It is more than just the motor internals, but it is far from everything.

edit: https://www.chevyhhr.net/forums/problems-service-repairs-42/07-09-10-11-powertrain-parts-coverage-list-22231/ If it is an 07 or 08, motor mounts are covered under the 100K warranty. If it's something else, who knows if it's covered.