I cleaned and oiled my K&N Air Filter in my 2000 2.7T a while back, and a while after that my car started acting sluggish. I have heard that over-oiling the filter can ruin the MAF (or does the 2.7T use a MASS or w/e it is, help with that too lol) causing fault. I am wondering if there is a way to check to see if it is ruined by physically examining it, and what I should look for. I have been thinking that its a possibly tear/break in the boost hosing somewhere because when it spools up it creates a loud whooshing sound instead of the whistle that it created when I first got the car, but could over oiling the intake be the problem instead? Thanks for all the help!

 

The air flow sensors hate that intake oil. You could try cleaning your MAF with some electronic cleaner that you can get from autozone. The oil from the K&N can build up fast and hurts the cars performance more than one would think.

 

MAF is located at the top of the air box. It is screwed with (2) tamper resistant torx screws, so you would have to go buy one. Or I heard people using vice grip, but I don't recommend it. Anyway, just take a look at it and see if you notice any oily residue. You can use electrical parts cleaner or pure alcohol to clean the MAF. Just spray with cleaner or dip and shake in alcohol and let it dry for awhile.

I say clean MAF and see if it works better instead of start getting into expensive diagonostics and repairs.