04 E320 CDI rattle on accelerate - cats?

[ca-uk]

I've done a quick search on here - i think the diagnosis may be a cat on it's way out, but thought i'd see what the consensus is.

When the engine gets warm - i.e. > 80deg, with the windows open, when accelerating then i can hear a tinny rattle - only seems to happen up to about 1800rpm and then i think it disappears/i can't hear it. I also cannot hear it when not accelerating - i.e. when foot off accelerator. I can try and record it, am away at the moment so would have to do it when i'm back on proper internet..

Thoughts?

 

[Bobby Dazzler]

It's certainly a possibility.

My experience of rattling cats:
http://www.mbclub.co.uk/forums/general-discussion/29245-thinking-buying-ml-2.html#post276799

 

[jorjXmckie]

I recently had a loud tinny rattle from my E270CDI that turned out to be a heat shield come loose and rattling on the exhaust pipes; mind you, it was loud!
I suppose it's possible yours is just loose and not dropped down.
Just my 2 cents....

 

[MPK]

Mmmmm...Had something similar on my previous E300TD.

At tick over sounded like a penny was loose and rattling in the middle of the exhaust.

Turned out to be the Cat.

Check the heat shield and exhaust mountings first !

 

[ca-uk]

Is there more than one heat shield? Is it something i can check without ramps? I guess when the engine and exhaust is cool i could lean under and give things a wiggle? I've never had a cat go before, even on cars more than 6 years old, so is it a common failure?

 

[walsi]

Reminds me of a friend of mine who drove off down the road one morning and thought he could hear a cat making a right clatter. He stopped and oppened his bonnet and out lept a rather angry cat with half a tail
And on another note we have lost three cats but i'm sure that the black one living down the road used to be one of ours :bannana:

 

[ca-uk]

Anybody know the price of cats for this car? I'll have a mooch at the heat shields now we're back. It definately only starts when the car is warm - reminds me on my old e46 then the heat fins on the engine used to rattle together when the engine got warm, so i'm hoping it's just something like that..

 

[BlackC55]

Put it on a ramp first to be sure!

 

[ca-uk]

Thanks olly - ramps cost money so i was trying to find out the free way first

From sticking my head down and looking while pushing the accelerator then it sounds like it's coming from the front, underneath the engine rather than the middle where i think the cats are? And it definately only seems to come on with temperature..

 

[BlackC55]

I will check it for free if you wish. It will only take 5 mins

 

[jeremy 2516]

There is a heat shield near to the downpipe that you could check too .

 

[tich]

Thats a jolly good offer from Ollie just dont forget to take him some choc hobnobs i know he likes them been there.
Tich

 

[pake]

Did you ever get to the bottom of this rattle?

 

[streethawk]

Did you ever get to the bottom of this rattle?

Let's hope so as it's been 5 years

 

[HB]

Funny thread timing. I've just pulled off the near side heat shield above the back box because of the rattling. It's lovely and quiet again.

 

[toolman1954]

I have had a rattling offside rear heat shield for some time now and cannot see how to fix it other than dropping down the exhaust box, or even taking off the rear bumper. So last week before my journey up to Scotland I jammed a tennis ball between heat shield and silencer. Still there now after 400 odd miles and no rattle.
Steve.

 

[renault12ts]

^ Cool, man!