I have heard from 2 merc techies that spark plug wires are not usually the suspect, if anything it is only the ends on those wires that go bad, ask me how I know!! yup spent 144 on new wires only to find out that I didn't need them. I had the exact same symptoms, turned out my problem was timing was way off, and the main cause was an air leak under the intake manifold. I am not saying that is what is wrong with yours, could be that, a vacuum leak, an injector... most likely not the ignition wires.!! Where are you located?? look in the Good MB shops section and see if there are some highly recommended shops by other members??

__________________
**A few Hondas etc... etc... Not Worth Mentioning**
83 Euro W126 380 sel Money Pit (Sold)
91 W124 300e 2.6. (Sold) 3.0 Motor is Much better!!
93 BMW E34 Touring Wagon (Sold) Sweet Car!!
91 300e (Just 200k with Ease.)Best car ever ???(Sold)
90 420sel (Black with Tan Interior) Best car ever!!!!!!!