Noisy new catalytic converter

The check engine light was glowing on my Honda civic. I had it checked out at the Honda dealership and they told me I had a bad catalytic converter. I had a new one installed yesterday, but since then my car has been making a noise every time i accelerate. They told me that this would happen for a few days and then the noise would go away. Can someone advise me whether this is supposed to happen? or did they just do a bad job at it? iam worried !! HELP

There should be nothing making any noise after a catalytic converter is replaced. Take it back and tell them they screwed up somewhere.


I agree. There is no reason for a new catalytic converter to make any “noise.”

Something is wrong. Make them fix it!

It may be the heat shield is loose after the installation. Bring it back and have it addressed.

We don’t worry too much about exhaust noise. By now they should be able to tell if there is an exhaust leak.

What kind of noise? Is it a tinny vibration like a heat shield or maybe a high pitched noise that sounds as if rocks are rattling around inside the convertor? If the latter I would suspect the substrate inside the convertor is broken into pieces.

Its a vibration - but its a bit loud. And it gets higher whenever i accelerate. If something in the converter were broken, wouldnt the check engine light go on? the car is running good, and the check engine light hasnt come on. so iam hoping whatever it is, is not a big deal.

Sounds minor but they need to make it right.

Hey who cares why, they need to figure out why and how to fix it, it is there problem, don’t make it yours. Your problem is getting it back to them and make sure they fix it.

Its a vibration That sounds like a five minute fix and they should take care of it for free.