i have an 87 420sel that displays a problem. i'd appreciate anyones positive input. when the car is cold and just started it does not smoke, but if i sit at idle for several minutes to warm it up or if i stop for any length of time while it's still cold it bellows out smoke so thick that that you can't see through it as soon as i start moving. if i just start and go this doesn't happen. it uses no oil and not a lot of transmission fluid between oil changes (3000 miles). once warmed up it doesn't do this either. could anyone give me a tip as to what might be causing this and where to look for the part that might need to be replaced. thanks
Question ?? 420 SEL
Oct 11, 2003
4 Replies
It uses transmision fluid?
I had this problem on my 84 500 sel. It was the modulator valve on the side of the transmission. Inexpensive problem
Pa ul
84 500 SEL
My 450SL had a problem like that. It would also blow a huge cloud of smoke at idle if stopped on a steep nose down incline for a moment. It was the valve guides. Had them replaced and has not done it since. It would only do it once after starting the car and not every time. Usually i would get about 1-2 miles from the house and it would release a huge white/light blue cloud from under the car.
Probably your valve guide seals are worn....could be the modulator, check it, but I would bet on the valve guide seals.
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