Some of you may have known that I'm using the Evo Highflow setup and experienced a drop in bhp/torque. A couple of reasons suggested by some are :
1) Bad MAF
2) Insufficient incoming air volume
3) Leakage
To prove (2), I wanted to replace the air filter with a double layer of fine wire guaze over the intake pipe with the intention to dyno the car again afterwards. Reason being the supplied K&N filter has a much smaller surface area compared to the stock paper filter. Hence, if I experienced a power hike upon removig the filter, the fault probably lies with the filter's smaller surface area.
However, upon removing the filter, the idling immediately became unstable and was hunting. This goes away once I put back the K&N. The increase in airflow obviously caused some undesirable effect. Is this supposed to happen? Is this a sign that my MAF is screwed
Under normal circumstances, a less restricted intake will result in higher idling but not supposed to cause unstable idling right?
Hope someone can point me in the right direction
Finally, is there any sure way to find out whether my MAF is screwed?