I recently went to service my wifes Lincoln because of rough idling. I cleaned the MAF and thottle body, the intake inside the engine is filthy black, I ended up replacing the idle control valve, anyway the source of the problem seems to be ommiting from a Purolator air filter, I love Purolator and always have used them faithfully but this the last air filter I buy from them. It looks like it melted or diseingrated. Iam going to have my wife post the pictures, Iam going to call Purolator and complain, the filter was in service for 10,000 miles which isnt over due. I usually go 12,000 or a year. The paper is intact, but the black part that sealed aginst the airbox that is ussually shiny, is all crusty and disinergrated. I never cleaned the thottle body or MAF before so it wasnt a chemical reaction, Iam thinking I got a old filter, and I got it off the shelf at Advance, because i dont stockpile these, they are the big round ones and a bit pricy. I have a Napa in it now. I hope that black [censored] cleans itself out of the engine, I hate spraying cleaner down in the engine, I got the thottle body spotless.