akshay67

I fitted a KN57i induction kit to my MY99 today - I'm sure its made the car slower, but its worth it for the noise!

The only thing I'm worried about is the MAF sensor going - hpw would I know its gone and how much does a replacement one cost?

Dark Blue Mark

Induction kits sap torque IMO and do nothing but lean the mixture out. The K&N is the best one, however.

You could either fit an AFR meter, or reset the ECU and see if the idle goes all over. You will notice these effects straight away if you damaged it while fitting.

If I owned a MY99 again, id swap the MAF for the better one you can buy, as a matter of course.

MB

scooby-dooby

If your MAF sensor was going your engine would idle between 500 and 1000 rpm erratically. New ones from Subaru cost £70 inc Vat.

john banks

As well as leaning out the mixture slightly they also cause the base ignition timing lookup from the map to be from a slightly lower load zone and so run more timing on full load.

You lose torque from the lean condition (exacerbates a leaner area in the map particularly on P1/STi5/6 which can run -4 degrees or worse and det on Optimax with a decat and K&N in hot weather even with no boost spikes, the UKs don't go that bad just lose a bit of torque), and you tend to gain a little power from the lean/retard.

chrome

aha...

good info john.. think my MAF is responsible for recent problems looking at your reply.. i love the search function