I had a very similar problem with my 94 E320 Wagon. It also turned out to be a bad coil. Mine was a bit difficult to diagnose because no codes were present. I know there was a production run of coils with a rather high failure rate, I'm not 100% sure but I think they are identifiable because they are blue in color. Another common cause for misfire is the coil to plug connector, lots of searchable information on this. As always, posts by Arthur Dalton are always spot on. Fortunately, niether of the above are very expensive, coils are about $75 from our site sponser, plug connectors are less than $5. I would think not more than 2 hours labor would be reasonable for diagnosis and repair.

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1994 E320 Wagon, 230,000 miles
1995 E320 Sedan, 106,000 miles
1994 E500 Sedan, 79,000 miles