1994 Mercedes C220 A spontaneously switches off when engine cold

I have a 1994 Mercedes Benz C220 auto 190 000 km. The car spontaneously switches off several times ONLY when the engine is cold - this happens only for the first two to three minutes since initial startup (thereafter the car runs perfectly). It cuts out when I I'm just about coming to a stop; or sometimes even when just at idle; however it is able to start immediatly after cutting out. On a cold engine, the engine idle speed is approximately 700 rpm - the same as when the engine is warm (Is it supposed to idle higher with a cold engine?) The car does not cut out at all after these first few minutes of operation - thereafter it drives beautifully and trouble free. The car has a full service history. I had the engine wiring harness changed at 120 000km (2003) as it was faulty, other wise no other significant problems. Last fuel filter change at 170 000km, air filter changed at 180 000km. Engine maintains normal temperature, cooling fan comes on appropriately. I do not wash the engine bay so as to avoid wetting of electronic components. Please assist with the diagnosis and solution.