I recently have a strange problem with my W126 380SEL. When the car go down hill for a long distance (3 Kms or more), once the car is level out, it gives a lot (I mean a lot) of white smoke for only about 10 seconds.

I strongly believe it is coolant burning because the coolent level will drop after that.

I also find soem coolent stain near the thermostat.

Am I up for a big repair bill? Please help.

Regards,
Michael Tse