Slk32amg catalyst

[Matt32AMG]

Is starting to disintegrate on the near side pipe according to MB. I had detected a slight resonance when driving yesterday and thought I’d get it checked out. A Whopping £1088.00 to replace just the one.

On the SLK32AMG there are two pre Cats and then two catalysts before both pipes connect into the centre resonator. Clearly this is making the exhaust system on my car out of the realms of Kwik fit and the like so any suggestions welcome as this strikes me as a bit of a leg up .

For the record, this will have been the first time I will ever had to replace a Catalyst on any car I've previously owned. Perhaps I had understood wrongly that Catalyst are usually good for a good while, especially as its a stainless system throughout and the car has only just done 38000

Regards

 

[Bobby Dazzler]

Is it the precat or main cat that's gone?

 

[mr. shr]

I thought CATS purred for about 100K?

My W202 ones have recently started to rattle now, with 94k on the clock.

 

[Matt32AMG]

Is it the precat or main cat that's gone?

Hi Bobby,
to quote MB its the near side CATALYTIC Converter has started to break up. That'd be the main one not the precat.

I've done some research and I think CKSPerformance do a Hi performance one at £395 + Vat but then my concerns are that if you do one you gotta do both else there could be potential back pressure imbalance issues? That said it should give me another 20BHP if I've read that correctly

 

[Matt32AMG]

I thought CATS purred for about 100K?

My W202 ones have recently started to rattle now, with 94k on the clock.

That’s kinda what I thought, however having just spoken to MB about this matter, if I bought a new Cat from them, they'd only give me a two year warranty, which equates to 10,000 miles top in my case Ouch!! And at the fitted cost of £1088 . Not exactly peanuts.

Ok I could get it about £80 cheaper if I fitted it myself and that just about pays for an oil change on the CLK.

I suppose the upside if there is one, is that breakup is slow so I have some window of opportunity before I have to sort it urgently as the symptoms have only just started to show. I mean it wasn't flagged when my car had it's last MOT at the end of July this year.

 

[cl55 amg]

I would do a search on CKSPerformance (if that's the one in Watford) they have received very mixed reviews..

 

[mr. shr]

Well I'm on the look out for a replacement for my W202. But a genuine MB one will cost about about what the car is worth so I'm looking for an aftermarket one.

However, I've been told (by my indy and guys here) that an after market one will not sound anywhere near as good as original MB ones. (Not a big deal as the W202 isn't worth much now anyway.)

See what others say on here, but you might want to take that into consideration as your car is an AMG and sound (I gather) is quite important.
So although cheaper, an aftermarket one might not give you the same satisfaction as a genuine MB one.

 

[Matt32AMG]

I would do a search on CKSPerformance (if that's the one in Watford) they have received very mixed reviews..

Yeah I have heard this and yes they do appear to be the same guys you mention based in Watford. Guess I have to ask the question though

 

[Matt32AMG]

Well I'm on the look out for a replacement for my W202. But a genuine MB one will cost about about what the car is worth so I'm looking for an aftermarket one.

However, I've been told (by my indy and guys here) that an after market one will not sound anywhere near as good as original MB ones. (Not a big deal as the W202 isn't worth much now anyway.)

See what others say on here, but you might want to take that into consideration as your car is an AMG and sound (I gather) is quite important.
So although cheaper, an aftermarket one might not give you the same satisfaction as a genuine MB one.

Its a reasonable argument you put forward regarding the MB option Mr. shr. I guess I'm kicking back at the mega bucks that they are wanting for the part in question. You know I'm even considering, if its worth my while that is, going to Germany if the price is right and have a long weekend away while I'm at it. Then that starts to justify the expense

 

[BlackC55]

Is it the cats in the centre that are breaking up?

You have two cats on each bank. If it is the last two that are rattling just remove them by cutting them out. It will still pass an MOT, be more powerful and have a slightly better engine note all for much less than 1k.

If you need any more help as to which cat is the problem just shout.

 

[Matt32AMG]

Is it the cats in the centre that are breaking up?

You have two cats on each bank. If it is the last two that are rattling just remove them by cutting them out. It will still pass an MOT, be more powerful and have a slightly better engine note all for much less than 1k.

If you need any more help as to which cat is the problem just shout.

Yeah its not the precat but one of the Main Cats thats started to go. (near side) .. If your suggestion is on the money and it'll still get through the mot, we'll go for that option and go on a short holiday instead Is that something you can do as I don't weld?
Cheers
Matt

 

[BlackC55]

Sure. Done it a few times now.

 

[Matt32AMG]

Good stuffl
I guess the next question is when? MB say it is not critical to sort it as yet, but to keep an ear to what is happening. That said I don't want to be in a situation where the Cat disintegrates and blows back debris into the Motor. (A long shot I know, but better be safe than having to rebuild the engine)

Cheers
Matt

 

[Bobby Dazzler]

I'd always thought that you could get away with the pre-cat but not main cat. If you can do it the other way round, it sounds like a relatively cheap - and worthwhile solution to the problem.

Problem fixed + Nicer sound = Happy bunny!!

 

[Matt32AMG]

I'd always thought that you could get away with the pre-cat but not main cat. If you can do it the other way round, it sounds like a relatively cheap - and worthwhile solution to the problem.

Problem fixed + Nicer sound = Happy bunny!!

Well if its a flyer as BlackC55 says then hey happy days! Plus an extra 20BHP I would've thought, as that allows the engine to breath more easily.

 

[Adam230K]

20bhp talk is rubbish. They will never create a better cat than AMG. If you remove them you will get the best result and even at that, you'll notice a slight gain in torque to give u a max of 5bhp realistically.

And its true, it can pass with one pair of cats (2, not 4)

 

[cl55 amg]

would this not cause the engine light to come on as it would interupt the pre/post sensors?

 

[Matt32AMG]

20bhp talk is rubbish. They will never create a better cat than AMG. If you remove them you will get the best result and even at that, you'll notice a slight gain in torque to give u a max of 5bhp realistically.

And its true, it can pass with one pair of cats (2, not 4)

Is that AMGs justification of charging £1000 for it? Its only the profit that makes it expensive

With regard to increase in power, there should be a difference in that the engine can breath more easily, exact gains is always subjective and without putting it on a dyno who can say exactly? To be frank I'm not that bothered, but given that some companies claim with their high performance cats installed, a gain of 20BHP is normal I take with a pinch of salt, that said I'm just working on the basis that with out the retriction of CATS all together, it's gotta be close to that.

Passing an MOTwith just two precats I'm frankly amazed at but hey live and learn

 

[Matt32AMG]

would this not cause the engine light to come on as it would interupt the pre/post sensors?

Not a clue, but then if black C55 has done it a few times without issues who is to argue. That said I do see where you are coming from

 

[Adam230K]

BlackC55 is right, you can pass with only 2 cats. A friend has a BMW 540 with only 2 cats, where originally it had 4. He's also removed the silencer and i remember noticing a bit of a difference when he did, especially from low down in the rev range.