CLK-Class (W208) 1998-2002: CLK 200, CLK 230K, CLK 320, CLK 430 [Coupes & Cabriolets]

Catalytic Converter rattle

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Old Oct 13, 2008 | 04:30 PM
  #1  
Gundo's Avatar
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From: Kansas
2001 CLK430, 2012 CLS550
Catalytic Converter rattle

So the first two converters closer to the engine are bad. Broken inside and rattling like crazy. I have a couple questions for you guys who have gone through this already.

Well, my car almost has 100k in mileage so warranty replacement is out of the question.

Has anyone replaced with aftermarket cats which would be cheaper?

Has anyone just gutted the inside of the broken cats and welded them back together? I know it won't pass emissions that way but not too worried about that. Will my computer go crazy?

What about just going strait pipe?

Any info would be greatly appreciated. Spending $600 a pice plus install is just something I cant justify on this car. This situation sucks pretty bad.

Thanks for any help guys.
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Old Oct 13, 2008 | 04:35 PM
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Dan Wang's Avatar
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E320CDI, CLK55, and a Smart
MBUSA just reduced the costs of cats within the past couple months. Check with them first. On a W203, I just replaced one for $600.
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Old Oct 13, 2008 | 04:51 PM
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From: london
ck430 2002
take them out and weld them back together thats what i did and problem sorted that rattling noise is annoying right? this happened to me so my mechanic took them out for me and the car runs like normal.
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Old Oct 14, 2008 | 12:47 AM
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A Magnaflow 59950 ($110) for the right side and a 59975 ($120) for the left. They're both metal substrate.
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Old Oct 14, 2008 | 03:27 AM
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1999 CLK320
Originally Posted by MarcusF
A Magnaflow 59950 ($110) for the right side and a 59975 ($120) for the left. They're both metal substrate.
i'd also go with MFs.
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Old Oct 14, 2008 | 01:57 PM
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2001 CLK430, 2012 CLS550
Originally Posted by MarcusF
A Magnaflow 59950 ($110) for the right side and a 59975 ($120) for the left. They're both metal substrate.

Will these two give me errors at all because of difference in back-pressure compared to OEM's? Also what size pipe is it that we have in line with the converters?

Thanks for the replies guys I appreciate it!
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Old Oct 14, 2008 | 03:38 PM
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From: in the car :)
02' brabus modified ML500,05' Lambor Gallardo, 02' CLK
i happened to my ML W163 last month. The cat was broken cause no flow ---> misfire, lost power. I brought it to a shop, the just cut off the cat, replace a new one ( OEM ) and weld them together. sound and perform like new. cost $250. FYI.
Also i replace a whole exhaust sys under my CLK. and it didn't mess up my ECU. cost $600 for cats, muffler...etc. OH I got them for whole sale price. ( Magnaflow muffler for my CLK cost $260 retail, i got it for $150)
Hope this help
kenneth
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Old Oct 15, 2008 | 12:46 AM
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From: SCV SoCal
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Originally Posted by Gundo
Will these two give me errors at all because of difference in back-pressure compared to OEM's? Also what size pipe is it that we have in line with the converters?

Thanks for the replies guys I appreciate it!
Cats don't cause a CEL because of lack of back pressure. The ECU has no way of determining how much back pressure is present. When a cat causes the CEL to illuminate, it's because the signal from the secondary O2 sensor is too close to the signal from the primary sensor. That points to either a dying or dead cat (burned out substrate). A dead O2 sensor gives the same OBII failure code as a dead cat.

The part numbers I listed are for a 2.25" pipe, which is the same as the pipe on your car.
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Old Oct 15, 2008 | 08:42 AM
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That was exactly my problem!! I was doing searches and calling all around trying to find the best cats for the money and right when I was about to buy I went to a muffler shop to see how much it would cost for him to do the job.

I was lucky enough that the shop was honest. He checked my cat out by knocking on it with a hammer and found that the heat shield closest to the front cats had spot welds that were cracked at 3 corners. It was only held on my one spot weld, therefore it was causing the metallic can (??) sound that most were describing as my cats being dead.

I even had the CEL light that stated that my O2 sensors, MAF or MAP sensor were bad. So after I found out that the cats were not making noise anymore I replaced the O2 Sensors with the bosch universals which were WAY cheaper (160 for both in front) and now the car runs like a new car again. My gas mileage went from 21 HWY all the way to 27-28 HWY. I drive to Houston quite a bit now (210 miles one way) and it is much more enjoyable driving there with better gas mileage.

Greg
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Old Oct 23, 2008 | 10:48 AM
  #10  
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From: Atlanta, GA
01 CLK430
I have the same problem, but am lucky enough to be under 70K, so will replace it through the warranty.
However I did look for original ones at MB and through the internet stores.
MB was asking for the right side over $700 and for the left over $400.
The cheapest on line was from Buy MB Parts dot com – they quoted over $400 for the right side and over $300 for the left.
By the way, I just purchased 16 FR8DPP33 spark plugs from them for $70.06 and added Bosch Fuel Filter for $34.63 to have my order over $99 to get free shipping (on catalog items).
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Old Oct 23, 2008 | 01:04 PM
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2000 CLK430
Originally Posted by kyxapka
I have the same problem, but am lucky enough to be under 70K, so will replace it through the warranty.
However I did look for original ones at MB and through the internet stores.
MB was asking for the right side over $700 and for the left over $400.
The cheapest on line was from Buy MB Parts dot com – they quoted over $400 for the right side and over $300 for the left.
By the way, I just purchased 16 FR8DPP33 spark plugs from them for $70.06 and added Bosch Fuel Filter for $34.63 to have my order over $99 to get free shipping (on catalog items).
If you are under the 7 year 70K miles then MB will replace it for free. Go to the stealership and have them replaced if they are rattling.

Greg
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Old Oct 24, 2008 | 02:01 AM
  #12  
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From: FL 33325
2002 CLK 430
Originally Posted by gregory13lil
If you are under the 7 year 70K miles then MB will replace it for free. Go to the stealership and have them replaced if they are rattling.

Greg
8 years or 80K....state low
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Old Oct 24, 2008 | 02:27 PM
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Originally Posted by J56BP
8 years or 80K....state low
OOOpps Yeah thats what I meant LOL
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