wingnut

My 1995 C220 starts right up if its cool, but just grinds away and finally catches when the car has been sitting out in the sun at 90+degrees. Once its running ok, I can shut it off then back on again no problem. Also, while sitting at idle it will occasionally have a minor seizure and the RPMs drop out, then recovers. The whole episode lasts only a fraction of a second, like someone quickly turned off the ignition and then back on again. No other hiccups. It will have these episodes once every few minutes of idle time. It has never stalled completely. Someone mentioned a fuel pressure regulator could be causing this. Fresh plugs and fuel filter. Any ideas?

Untertürkheim

Sounds like it could be a fuel pressure issue. I had a similar issue on my 560SEC. One way to check (not foolproof) is to turn the key to the on position (where you hear the fuel pump priming the system) and then back off without starting about 10-15 times before trying to start. If it is a pressure problem, the symptom will be lessened by the built up fuel pressure.

Based on what you have said though, fuel pressure, either the pump or pressure regulator seems to be at fault.