Catalytic Converter

[Rocky]

I have a 1997 C36 AMG with 106,000KM.

Just wondering when do I know I need to change the Cat on my car. I have an exhaust noise when cold and the dealership said I needed a new cat.

New cat at 106,000KM?

[Ali Al-Chalabi]

You need a new cat when your vehicle's emmissions reach unacceptable levels. New cat at 106,000km? Seems pretty early for a new one. I don't know how it is in Canada but I know here in the US we have a federally mandated 8 year 80,000 miles (don't quote me on the exact numbers, but it it something like like) emmissions warranty on cars.

[royaiii]

I had my cats replaced on my 99 S420 w/ 45k miles. The cats themselves arent usually the problem at this low mileage. Something goes wrong to ruin them whether it be MAF or O2 sensors, or both. My car is from Canada but I live in LA. The 8 year warranty covered this problem. Did your service advisor say it's covered. By the way take out that K&N Filter before giving it to them because it would suck if you had to pay for an 8000 job due to an air filter. Since the rust from the snow in Canada rusted my muffler and resonator, they had to replace those too. If Mercedes doesn't cover it, then it will cost a lot of money to fix. Perhaps you should decide whether it is that important to stop an exhaust startup noise. Get a smog check and compare it to your early tests, to see if you are going to fail emissions.

I would say if you have to pay out of pocket, it will cost at least 8 grand to fix at a dealer. Each cat is 2500 a peice. I bet they have to do a gazillion tests on it and at least 10 hours of labor because of the rust. And don't expect the process to take 2 days, mine took 17 days. I bet some parts are AMG specific and must be special ordered.

It's strange that Canadian Mercedes have cat problems. Perhaps someone should post a poll.

[Rocky]

I'm not sure if the rust is the problem. The advisor said the cat had cracks at the welds and he was puzzled. I asked about the emissions warranty and the foreman OK'd the warranty so i'm getting it done for free.

I had the K&N in for a month or 2 before my MAS went bad. Consesus tells me the K&N's oil was clogging the MAS sensor or the K&N was not cleaning properly so I took it out.

The emissions warranty in Canada is 8 years or 130,000km. I think.

[royaiii]

Well you're set. But I bet you they can't reuse the muffler and resonator once they try to put it back on the new cats. The salt really corrodes the flanges. Mercedes should protectors covering these components from the elements. This winter I will go for my smog check and I will really see whether the new components improved emmissions. If they do then I suppose it is a good sell point once selling the vehicle. Since other cars have some wear and blockage on their exhaust components.