MAF sensor sits after the evap line in the throttle body, so that would not show you anything useful. The car should run fine without the air cleaner, any leaks before the throttle butterfly valve do not really matter.
Check your o2 sensors after the car enters the closed loop - they would constantly show “lean” in proTune2 and you would eventually get CEL, as ECU would reach the upper adjustment limit. Then you definitely have an intake (or exhaust) leak :-)
Did you remove headers, when drilling out your exhaust? New exhaust gaskets?
Last edited by kankeL; 18/10/20 04:53 PM.
