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.

I replace lots of ignition wires on M112/113 powered MB's with over 40,000 miles. The good news is that they run like new afterward. The bad news is that the wires aren't cheap.

my guess is your MAF might be on its way out. try cleaning it or replace it next time u get new air filters

__________________
Current cars:
2001 MB E55 AMG
2003 Honda S2000
2000 Honda CRV

Gone but not forgotten:
2004 BMW 325i 5sp sport
1999 BMW 540i sport
1997 MB E420
1995 BMW M3 coupe

causing an arc from a plug wire to a ground. When air is moist, it becomes more of a conductor. Put car in a dark garage and run engine while idling roughly. Look for arcing off of plug wire.

Hi, Folks,

the rough idle turned out to be a miss on the #6 cylinder. My Indi, World Foreign Car in Richmond VA, replaced both spark plug wires and everything is fine.

Thanks for your help.

Steve