HELP - CLK320 Catalytic Converter rattling.

[14Ben]

Hi Everyone,

I have has a rattling noise coming from underneath my 20,000 miles, FSH, 2002 W208 CLK320 for a week or two now. It has been getting progressively worse so I took it in to my local MB garage earlier today who put it up on a ramp to diagnose.

They have informed me that the inners of my left Cat have become loose/broken up and it will need replacing. I have attached pics for you to see although there is obviously no indication of the problem from the outside.

They are looking into whether it would be covered under warranty as a MB good will gesture. If only the left Cat has gone would they replace both (as they lie next to eachother) or would only the damaged one be replaced ?

If they will not cover the work under warranty is it going to be an expensive issue for me to deal with, and can damage be done if it is left as it is for a few weeks ?

Any advice would be more than welcome !

Thanks,

Ben

 

[jaymanek]

im afraid cats breaking up is one of the side effects of having a car with very low mileage.
They dont get time to warm up properly on the short journeys and hence this is what happens.

If you want to skimp then you can get universal cats.

the other option is to cut up the cat and take all the rubbish out... not illegal as your CO reading will still be within limits.

or of course relace the cat which will not be cheap. for best prices you can source OEM quality parts from euro car parts or GSF.

 

[14Ben]

Thanks so much Jay.

If I were to replace the Cats but continue with my short journeys in the car could I expect the same thing to happen again ?

What is it about short journeys and not warming the Cats up that causes them to break up ?

What a pain !

 

[jaymanek]

im sure someone who will be able to provide a technical breakdown in response to your question will answer but basically short trips mean the cat is warming up and then cooling down quickly... this causes it to break up over time.

short journeys in general arent good for many parts of the car.. the main ones being the exhuast in general.. also brakes, engine....

 

[recycled]

im sure someone who will be able to provide a technical breakdown in response to your question will answer but basically short trips mean the cat is warming up and then cooling down quickly... this causes it to break up over time.

short journeys in general arent good for many parts of the car.. the main ones being the exhuast in general.. also brakes, engine....

messed up either way. Long journeys hit you in the pocket, and small journeys do the same

 

[bigtee]

Condensation builds up in the system and requires heat for it to evaporate, usually the rear silencer is the first to go as it is further away and they corrode internally.

When replaced take it for a good thrash now and again to move things on there way!