ML320 1998 Catalytic converter

Of course he wants to use the best and most expensive...He makes more money that way....O2 sensors are O2 sensors MB uses Bosch. No big deal there. I used after market cats on a 92 Corvette and they worked fine and the fit was correct. I got these from an outfit in Texas. I believe they were called discountconverter or something like that. I would go with the after market replacements and have a good mufflershop install them in case any tweaking needs to be done.

Peter

How do you know the very cheap ones aren't counterfeit?

Loads of dangerous junk parts about.

DAS

For direct contact replace nospam with schmetterling

Thanks for the reply Peter,

Unfortunately OBD2 came in around 1996. B4 that aftermarket Cats seems to work perfectly and have no problems passing the State emission tests. However, after 1996 "most" aftermarket CATS seem to quickly give "errror" message on a car's internal computer. The emission test PCs plug straight into the car computers and download all the "error" messages. Any such messages relating to the CAT mean an instant test FAILURE. Doesn't matter how clean the actual emmisions are out of the car's tail pipe, it's the computer "error" messages which count!

DAS,

Yes in any aftermarket equipment there are good and not so good suppliers. There are a number of well known reputable CAT suppliers and their equipment is probably as good as ANY MB piece of equipment in quality standard. Problem is MB/Bosch seems to be hiding some "secret" re the way the sensors work which increases the propensity of receiving "incorrect" error messages.

What I am seeking is the knoweldge base of people here. Does anyone have real in depth experience of this issue and any particular recommendations re supplier.

The garage I use I have knwon for more than 15 years and I do not believe they are deliberately taking me for a ride. They tell me that their experience of CATS in cars after 1996 means they get too many "error" messages down the road which can only be erradicated by using the original MB equipment. As I say I am looking for input from people who perhaps have found a better solution from a supplier which can certify CATS for post 1996 OBD2 compatibility. Thanks.

This is pure FUD. There are many fine aftermarket replacements available. You would never get a "counterfeit" unless you want MB original. No one counterfeits aftermarket parts as they aren't as over priced.

Find a good local exhaust shop (ie not midas) and let them handle it.

Marty

In that sense I am inclined to agree with you but I still wonder why a non-MB part should be so much cheaper. We're not talking 25% here.

The costs (material ands labour) can't be that dissimilar, can they?

(Any replies besides "MB/Bosch are ripping us off" welcome...)

DAS

A mate of mine has a CLK320 (208). His cats failed July last year. Didn't like the price of MB replacements so fitted some after-market ones. Since October his car's been in my workshop 4 times to have to Engine light turned off. Each time for a cat related fault. When I inspected his cheap n cheerful cats, they were half the size of MB ones. Told him to get the MB ones. So he's actually spent more!!!! Never seen a modern MB run right with cheap cats/exhaust systems.

Yep, that's the concern. The manufacturer CATS are absolutely huge in length so getting a small piece and hoping for the best is NOT a good diea. I am just surprised that no solid after market manufacturer hasn't come up with the goods yet. At least I can't find one....yet.

Come on guys this is not really a black art......After market converters should be fine if they are made to the correct specification and are not some generic undersize bolton.. Specific trouble codes for Cat performance are identified by trouble codes P0420 to P0434. No mystery here...if the cat performance is out of spec and is not working correctly it should set a trouble code. This supplier is not the least expensive but they deal in all MB parts. For a 49 state cat they want $525. for a Cal cat they want $595. I have had good luck bying from them. They also have a very nice catalog with part numbers & pictures for varuious MBz

PerformanceProducts4Benz.com

Peter

Sorry..here is the correct URL

Interesting website. But I see no mention of catalytic converters?

Obviously the ones available in America are just as good even though they cost half or less. Voodoo economics? Cheap illegal labour? Hand-made under contract in the back street of a Chinese suburb?

DAS

For direct contact replace nospam with schmetterling

Well here is an update:

I had the ML "in" for the Harmonic Balancer (it was replaced) and the MB service people agreed the LHS CAT is a "gonner". My research shows me that 1999-2001 CATs are subject to mandatory MB inspection related to a "leak" I think it's campaign no: 2005060014 September 2005. 79,119 vehicles affected.

Hmm this leaves 1998 owners (like myself) out in the cold (Warranty is

8 years or 80K miles and I am 85K). What surprises me is that the 1998 CATS must be different from the 1999 onwards (or they would be subject to the before mentioned inspection/recall). So why is my 1998 CAT in such demand that it is back ordered from Germany with expected one month delay? Is there a problem with the 1998 CATs that MB has not yet acknowledged?

Anyone else with a similar problem?