Had a long drive yesterday in the cold rain. When I parked I noticed what looked like steam coming out of the grille on the right side (from sitting in drivers seat perspective). Continued for a bit after the car was stopped.

Clearly wasnt a mechanical problem and car restarted fine later.

Has anyone else ever noticed this?

 

Not so far. I am at almost 20K miles on my E550.

 

Happens when I go through car wash...engines just get so hot any moisture on grill turns to steam...nothing to worry about