Nick White

Having this issue with a rattle/knocking/pinging sound. been going on for a couple thousand miles, isn't getting any better or any worse. I've searched the forums but I can find one that's the same or with a solution. The rattle happens at idle to about 2200rpms and then it goes away. the video is pretty much right under the driver's side cat while I rev it to about 2k. The sound doesn't seem to be coming from under the hood, just under the engine, I can't even hear it under the hood. sounds like a popping/knocking sound. Does anyone have the same problem or know what it is and the solution? https://www.youtube.com/watch?v=5lAKtvRF3VY&feature=youtu.be (wait until the car is revved a little in the video, you will hear the sound quite easily)

terribleone

I believe I have the same rattle (haven't yet found a fix). Do you have aftermarket cats? Or any aftermarket exhaust components?

PNW_IPL

iTrader: (5)

Sounds very scary. Im in no way an expert at diagnosing so ill refrain. But doesnt sound good. Weird is at idle that sounds healthy normal then gets weird.

2011-G

Your cats are loose - My friend's coupe had the same noise

Get this on the lift and you will figure it out

Nick White

That's interesting. I have yet to hear another G with that exact noise, all I can find is the muffle problem with the spot welds breaking (but I have a muffler delete and it's still there) I'll definitely look into that, thank you!

Nick White

UPDATE:
It is indeed the catalytic converter. the material inside broke and that is what the rattling sound is. will be replacing it very soon.

Botlerocketwar

Is there a TSB regarding this issue?

Anyone know if there are legit aftermarket CATS that are CARB and california compliant? I have the same issue on my 09 with 150k.