Check engine light on - suspect emmission control system on 1990 Mercedes-Benz 190E

My MB dealer suspects carbon builtup somewhere in the system and says replacement might be needed and cost up to US$4,000. It has 145k on it. Suggestions?

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1 answer 1 comment
The dealer sounds clueless. I used to work for Bosch who designed the Mercedes KE-Jetronic Emissions System and there are several routine things that wear out, like Oxygen Sensors ( $200 ) etc, etc. What is the code that is setting the Check Engine Light. if I knew that, I could help you with your problem. I have and do work on lots of Mercedes Emissions problems. I do Gold Shield Emissions work in N CA. where the State pays me to solve tough Emissions issues for people so they can get their car to pass the Emission Test and get registered.
How does one find out what the "code" is that is setting the light?