Blow off valve / idle issue

[AlpWhitE46]

Originally Posted by suprra_girl

It's an easy test you can do

Our cars are air flow metered, they have a little black box in the beginning of the intake. So it measures air at the intake, the ecu then sees that air and calculates the fuel for it. If any of that air is lost after the meter then the ecu will still put that same fuel in as it does not know it has lost it. Therefore engine runs silly rich and stalls.

In a map sensored car the sensor is measuring from the intake manifold, so if air is lost before then it doesn't matter as it measures at the intake manifold.

So, if the bov leaks on an air flow metered car it will stall or cause horrific rich problems. If a bov leaks on a map sensored car it will will calculate fuel and run fine.

hmm i see thank you..