HHoRange07

Greetings all,

What started as a faint hissing sound during acceleration appears to have gotten substantially worse. This noise which doesn't seem to happen while sitting in PARK has become what sounds like a plastic bag stuck in the air flow system. This noise is most noticeable in low gear and gradually quiets down as I reach freeway speeds and fourth gear.

It was time for a new air filter anyway so we threw in a K&N but this has done nothing for the noise. I reported this noise to a local shop which says it is an exhaust leak but they couldn't find it within my authorized time window. (I wonder if they can find it now that it's as obvious as being clocked on the head with a rubber mallet).

It is coming from the front of the car like maybe directly from the manifold but who am I kidding? I trust myself better with motorcycles as everything is easier to find. I had a friend ask me why my car sounds like a tank and if I had bought a new exhaust. If I had bought an exhaust that sounds like this, I would have taken it back!

Any thoughts?

Thanks,

Geoff.

843de

Might be the down pipe from the manifold, I've heard of them cracking on other HHR's. If you can get it on a lift while running you can pretty much confirm it. Another thing to check is the intake snorkel from the fender to the air filter housing, it can give you a snorty sound if it pops off. Of course it could be a cracked manifold or blown gasket between the exhaust manifold and head. Gotta get it in the air or up on ramps to really check anything in depth.

HHoRange07

Thank you "all" for chiming in on this. HEHE

As it turns out there's a crack in part of the catalytic converter assembly. The guys at the shop who replaced my front struts today noticed it. They also said that the catalytic converter is warrantied for 8 years or 80,000 miles mandated by the EPA which was confirmed by the local Chevy dealer today. So I dodged a major bullet with 73,000+ miles and have an appointment next Wednesday to get it taken care of.

Anyone under 80,000 miles should give theirs a once over so if it's starting to go you won't have to pay for the repairs later.

843de

Good catch on the cat, sometimes that emissions warranty is a very good thing.

Greybeard999

That's the flex pipe, it's just above the cat....... fairly common for it to crack there.