So this issue began when I started my 2011 HHR this afternoon. It started up fine but all of a sudden, it started sounding like a modified, annoying import car. When I would hit the gas to accelerate, the sound would get progressively louder. Engine sounds like a lawnmower engine. I immediately thought I might have a hole in my muffler or a hole in the piping. I was already headed to AutoZone to purchase a bulb for my turn signals and spoke to an associate and he asked me if the sound was coming from the front of the rear of the car. I told him it sounded like it was coming from the front. He told me it could be the catalytic converter. Any opinions?

 

Almost certain to be the flexpipe on the exhaust system. That's the accordian looking part of the exhaust pipe, up close to the engine.

Try this link for some good pics and info. https://www.chevyhhr.net/forums/how-...ex-pipe-31536/

 

It could be a hole in the fabric of space, but my money is on the flex pipe.

If you are still within 8 years 80,000 miles you might consider going to a dealer under the Federal or California Emissions Warranty. Technically the flex pipe is part of the cat. It is illegal to replace a cat within 8/80,000 except under warranty.

 

Welcome to the site, yes flex pipe! Yes 8 years or 80,000 miles ! Dealership warranty!

 

Yes that 8/80 federally mandated emissions warrantee can be great if you are within it. The catalytic converter on my 2007 dissembled internally, sounded horrible, but it was one month shy of the 8 year mark, so dealer replaced entire assembly under warrantee.

 

Mr. Masi has not returned.

 

He wanted opinions, not facts?