I have a 2009 chevy hhr. I have a gurgling hissing sucking kind of noise when i accelerate. Been trying for weeks now to find the sound and can not. My first guess was an exhaust leak but all gaskets in the exhaust system have been changed with new ones and also a new flex pipe welded on at an exhaust shop about a year ago. Exhaust system checked and smoke tested and no leaks found. It is only when i accelerate and alsom sometimes on cold start up. I can hear it when i'm driving the car and hear it even more when i go under a bridge or drive along side the concrete median. Have heard some aftermarket flex pipes cause a sound. I'm wondering if this is the case. Exhaust shop mentioned nothing to me about that possibility if it is indeed true. Could something be happening with the catalytic converters internally? Car does seem a bit sluggish on the start but no engine light. checked out the vac lines too and found nothing. the sound is driving me crazy and it seems to make the car sluggish a bit or maybe just in my head because of hearing the noise. Any ideas??

 

what engine? turbo or na

 

2.2 engine, not turbo and has 111,000 miles on it.

 

post a video