Agree with ps2cho. Since you may not know its maintenance history, the car should first have a good tuneup, taking note of the condition of the various components in the process (are the plugs fouled, do the wires arc, are the distributor contacts worn, etc.). Right along with the OVP, there are tons of threads about the correct plugs to use. Brand preferences abound, but everyone agrees that the plugs have to be NON-resistor type. Some guys have trouble finding the right plugs, but they're available through dealers and several I-net sources, including the forum sponsor.

__________________
1988 California version 260E (W124)
Anthracite Grey/Palomino
Owned since new and still going strong and smooth
MBCA member

Past Mercedes-Benz:
1986 190E Baby Benz
1967 230 Inherited from mom when she downsized
1959 220S Introduced me to the joys of keepin' 'em goin'

There are only 10 kinds of people in the world--those who understand binary and those who don't