Q: Slipping transmission. clogged catalytic converter? on 1990 Mercedes-Benz 420SEL

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had the transmission checked (test driven) but the mechanic said the fluids were good and he thought it was not operating properly through the catalytic converter (clogged). Please help. Can't afford all that replacement. Is there a simple way to clear the exhaust system without replacing the whole system?
(1) Answer
There's no good way to fix a bad converter. It's probably bad (if it really is) because of a failing oxygen sensor, coolant in the exhaust, or excessive oil burning and you need to know that the O2 sensors are OK and that the engine isn't using too much oil or coolant.
You can get a good muffler shop to install a high quality (& cheaper than OEM) replacement catalytic converter. Be prepared to spend $200 to $300, maybe more, for a good one. But before you do, get a MBZ specialist to diagnose it for you. if it's really a converter, that's real easy to diagnose but you need to be sure of the other items I mentioned. A misdiagnosis or a cheap converter will cost you a lot more. You don't need to replace the complete system to replace the catalytic converter, anyway.
Here's a directory link for you: