i noticed when i put on the slp lid the original lid wasnt in the grooves at the back it was on top the grooves.. could this have caused the poor mileage? i didnt get to run yet with the slp lid yet, we`ve been having alot of snow..

 

if it was sucking in air it could have sucked in some dust and dirt which could foul the maf. other than that i dont see how it could.

 

If you have an air leak before the MAF then the MAF will still get proper readings, ait leaks after the MAF can cause all sorts of issues.

Massey

 

okay cool, after the maf was airtight