2011 QX56 rattle

pjdavep

Active member
Joined
Feb 10, 2016
Messages
101
Reaction score
34
Points
28
Location
Jacksonville, FL
The wife came home the other evening and said the car is making a weird noise. I've had the 0420 code for a while and know I need to replace the driver side cat. I also have a passenger side valve cover leak that I was going to get fixed when it's time for the next oil change. The oil did look a little low from this leak, so I topped it off, but no change in sound that I can tell.

Here's a video. Any ideas? Could the cat have broken apart that is rattling?

Thanks!

Dave P.
 
I’d remove that bank 1, secondary cat-converter to inspect it and most importantly, to be able to inspect the primary cat-converter.
 
I was under the car earlier and there's only one bolted connection spot after the secondary cat and the rest are welded connections. May be a result of me going to a muffler shop to have them swapped out the first time (~125k miles). Guess I'll try to take it to the shop tomorrow, but I'm nervous that driving it may cause more problems.

update - it was the driver's side cat that started breaking up and was rattling, supposedly damaging the downstream cat too. $1100 later at the muffler shop, I have all new driver side cats and the noise is gone.
 
Good you caught that in time and better the debris went towards the secondary cat-converter and not sucked backed into the engine. You'd be seeing another 0 added to the end of that $1100 total had it gone the other way.
 
Back
Top