My 1989 190e 2.6 lost power and stalled on the freeway the other day. Had it towed home and tried to start it.

It cranks and sometimes stutters a few revs, but never quite turns over. I did notice puffs of white smoke occasionally when I stop cranking. I pushed down the throttle plate and found more white smoke accumulating inside the throttle housing.

The first thing I did was come over here and start searching for information.

So far, I found that the last indy shop had installed platinum resistor plugs as part of a tune-up. I quickly replaced those with the copper H9DC's. I verified that fuel pump 'buzz' at the right rear wheel well. I also found fuel in the line from the fuel distributor to the cold start valve.

In the process of nosing around, I broke off one nozzle of the thermo vacuum valve, but if I understand correctly, this is part of the emission control system and shouldn't affect starting.

Does the white smoke offer any clue as to what's going on inside the engine?