My evo just got a wash and wax yesterday and was running perfect prior to that. Tried to take out this morning and now suddenly its running very lean with sputtering and a rough idle. No water was put in to the engine bay, intake was dry. Anybody have a clue of what could be wrong ?

 

Sounds like a boost leak somewhere to me.

Check all couplings, vac. Lines

 

i ran it under my 93 octane rom and it idled better. Not sure how that was possible. Also problem occured immediately after the wash. Maybe water got somewhere.

 

Check your spark plugs. Make sure they are dry. Is there some kind of moisture coming out of the exhaust?

 

no moisture. Starting to think the wash was just a coincidence. Just got the p0171 code today so it probably is a vacuum leak. You guys think its safe to drive around with a vacuum leak until i can get it fixed tomorrow? Car feels almost feels like its misfiring as a result.

 

Pull off your coils and blow out any water or condensation where the spark plugs are. Same thing happened to me.