Hello guys,

For the past 2 weeks, my car has been making rattling noises in the first couple minutes of driving in the cold, but goes away later. I took a look under the car while it was rattling and noticed that my heat shields over the catalytic converter in the front right are very rusted and you can see them vibrating. Once I touch the heat shield with the end of the screwdriver the rattling goes away.

My question is: Should I replace the heat shields since they're mostly rusted away? How much do they cost? Are there two parts to the heat shield (clamshell?) Also, would it matter if I just let them rust away?

Thanks for all your help!

My car is 2007 G35x sedan with 64400 miles...I think it's a bit early for this kind of thing to happen right?

 

Nah, its common with g35....

I would replace it.... after all it gets rusted so that the catalytic converter its protecting doesn't..

 

Thanks, but is there a specific part that can be replaced? Is the only way to replace the heat shields is to get a whole new cat?

I searched online but I don't see a specific part for just the heat shields...

 

I had a service rep at a dealer tell me it can be replaced by it self.... but then again don't quote him cause he was a moron who thought my car needed a new tranny from squealing sounds caused by a worn belt lmao

 

Wow, sounds like an idiot...

Anyways, I'm looking at Infinitipartsusa.com and found this diagram:

http://www.infinitipartsusa.com/part...iagram=3841185

I don't find a specific part for the heat shields covering the cat. It looks like I'm out of luck...maybe I have to tie it down.

For anyone who doesn't know what I'm talking about, it's this:
Look at 2:45-2:55...the thin metal plates covering the cat are rusted away and it causes rattling noises whenever my car is running in the cold in low gear.

 

just take it to a muffler shop and they can probably have it welded back on a bit tighter as long as the sides that are held together are not rusted, btw i have no rust on my cat shoelds

 

Unfortunately the sides are not held together....maybe one side is but the other side is not...I'll just have the hose clamp them down...

 

anybody have rattles coming from a heat shield that are not visibly rusted at all from the outside?

 

Well, rattles coming from a catalytic converter that's not related to a heat shield is a pretty big problem. If you don't have a CEL then it should be fine.

You can try checking the welds on the heatshield to see if they're tight?

 

I'm almost 100% positive you can replace just the shields themselvves and yes I would recommend replacing them and not letting them rust away.

 

I called the dealership- there is no way you can replace those heat shields since they come with the catalytic converter.

I also called other muffler shops and they all say the same thing...Even the link I posted above doesn't have a part number for the heat shields on the catalytic converter.

The only way is that I tie them down with the hose clamp.

 

^ hose clamps should work fine, else just take it to a muffler shop they WILL find a way to somehow weld stuff together and keep it form rattling

 

Had the same problem - rusted heat shield around the catalytic converter.

What I did was tie it with a clamp and it work fine. Only problem (if you would call it that) is now my exhaust system has a ruffled sound to it. Almost sounds like a different car to be honest.

 

I had the heat shield rattle on my 2007 G35x and the dealer removed the heat shields. Since they had done that it sounded to me like an exhaust leak and the dealer insisted I was hearing things and that it was the loud VQ engine.

Last week I had enough and made them put it on the Hoist and inspect visually........the welds were separating on the CATs and had both replaced under warranty.

Now I'm rocking two new Cat's at no cost to me. Dealer showed invoice of the parts alone and it was over $2400.00 (Canadian).

Needless to say I'm a happy camper now!

 

Hmmm wonder if my heatshields r rattling too..