W210 Rough Idle

[shailey]

Hi, Folks,

I have a 2002 E320 with 68,000 miles on the clock. Last year, I began to notice a roughness or miss while idling on rainy days. The shop checked it over and couldn't find a reason for the condition. The problem just went away once the weather cooled off last fall.

Well, now it's back. Does anyone have a suggestion as to how to address this problem? There are no fault codes showing on my meter. Should I be concerned, or should I just consider this to be an idiosyncracy of this particular vehicle?

Thanks for your help.