No video, lost phone in Feb and had to get a cheap one with mediocre cam quality. Problem is still there, rough idle whether or not engine is cold. Opened up valve cover, removed rocker arms and sprayed penetrating oil on the valves and gave them a nice tap. Did nothing at all. I'm now wondering if that is even the problem. Anymore suggestions? Could it be something I am totall missing that is so easy to fix?

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1990 190E 3.0L

I dunno if this applies to your car but have you replaced the insulator behind the distributor cap? This is often overlooked, as noted in this Star article:
http://www.w124performance.com/docs/mb/M119/ignition_misfiring_STAR.pdf

I am still having the rough idle issue on my car, but I notice that it gets somewhat better when the car warms up....but not just warms up, but after the car has been driving around a bit in stop and go traffic in 100 degree weather and the temp gets hot enough for the aux fans to come on. Does that indicate something?

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1990 190E 3.0L

Issue was a stuck intake valve. removed all spark plugs and all fuel injectors and used a 20cc syrings filled with lucas fuel conditioner and sea foam and blasted it into the fuel injector ports to clean up and lubricate the valves

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1990 190E 3.0L

Nice work! Bet you're glad you found the issue.

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1991 300E 124.030 103.983KE 722358 03 412178
207K

1979 240D 123.123 250K (Project car)

2000 Ford Ranger, 187K

2015 Dodge Ram 1500 EcoDiesel 37K

You have no idea. I hated driving my car with that tough stumbling. I was so miserable. Now I have the smoothness of a true Benz and the acceleration is amazing. Glad it's fixed, I have a slight hiccup here and there, but not often at all.

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1990 190E 3.0L