I wonder if someone in the past has adjusted the fuel mixture there at the fuel distributor? Possibly a vacuum leak?

My 190E 2.3 runs like a dream most of the time, but now and then, will sit there and randomly mis-fire at idle at a traffic light, and then other times, run like a song again. I replaced the fuel pump, filter, and the accumulator, as mine was dripping fuel.

Do you know the history of your car, or are you in the dark like I am?

Good luck!

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My first Mercedes Benz. 4/6/07.

1984 190E (201 024) 2.3L four.