Just, thinking out loud hear... If it were true that the "partially clogged fuel filter" was leaning out the mixture, then why: 1) Doesn't the lambda system compensate for this? (Because the Lambda system doesn't work unless the engine is already warmed up??) 2) Why wouldn't the "partially clogged fuel filter" cause problems at high speeds when more fuel is needed? Hey wait a minute I do have some missing at high speeds, I think I'll just change the filter and report back to the group... D² & 6530 Dave Delman Anyway, if we assume that the fuel filter is partially clogged your car would be running leaner due to impared fuel delivery. It would possibly run okay when warm, but since the car NEEDS a richer mixture when cold, and can't get it due to the clogged filter, the filter coiuld cause symptoms only when cold. If it gets progressivley worse, eventually it would cause problems even when the engine is warm. -Joe Kuchan [Non-text portions of this message have been removed] To address comments privately to the moderating team, please address: moderators@xxxxxxxxxxx For more info on the list, tech articles, cars for sale see www.dmcnews.com To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/dmcnews/ <*> To unsubscribe from this group, send an email to: dmcnews-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/