I'm givin her all she's got Captain
 

I have an 86 300E, 3L automatic. I have had some studdering problems since i got the car almost 2 months ago, but yesterday it was so bad that i couldn't go over 20 mph. I have performed a tune up and changed all the filters, it gets a bottle of injector cleaner every tank of gas (hoping that my studder would go away). If you play with the pedal while trying to get it to go, it seems that it wants to try but nothing happens. Then all of a sudden it will take off and run normal for a bit.
I am new to MB's so I am looking for some advice as to where to look for the problem.

Do a search on OVP relay or even my name and look at my posts...
That should get you started!