[redline8000]

This might be a dumb question and I think I already know where this thing is, but can someone please explaine to me where the placement of the Mass Airflow Sensor is. I would like to get the torx wrench and get some cleaner and clean that thing tonight.

BTW my car is a 2005 M3.....

Thanks in advance guys & gals.....

[redline8000]

Hello is anyone out there???? Hello hello hello.... I hear an echo.....

[Bingo15]

Ummmm......I am afraid to anwser this. MAF sensor is very delicate. If you trace your plenum coming from your throttle boddies toward the air filter just past the 90 deg turn heading toward the front of you car there is a electrical plug connected to the ( Mass Airflow Sensor ). Shouldnt be too hard to unplug the wires while depressing the clip. Then unscrew the two screws holding the MAF in. It should pop out with a little wiggle/twisting while you pull. DO NOT TOUCH THE WIRES/RESISTERS.

[ArtM3]

http://www.realoem.com/bmw/showparts...20&hg=13&fg=20

[Doug Evans]

If your car is a 2005 why are you cleaning it already its not even a year old yet.

[ArtM3]

Originally Posted by Doug Evans

If your car is a 2005 why are you cleaning it already its not even a year old yet.

if it's got >10k miles, or he uses an oilable filter, not a bad idea...

the cleaner, the more accurate the reading (it measures by putting out a signal proportional to the difference in the currents required by an isolated reference resistor, and one cooled by the air stream...which requires more current to stay at a reference temp/power...)

so the cleaner the better...

[Antnee77]

$375 for a new MAF sensor!? Be careful, man!

[charon]

Aren't MAF's self cleaning? I recall reading in the BOSCH handbook that the computer will continue to send current through the MAF for a minute or so after every power off to burn off any dirt.

[Beowoulf]

Originally Posted by charon

Aren't MAF's self cleaning? I recall reading in the BOSCH handbook that the computer will continue to send current through the MAF for a minute or so after every power off to burn off any dirt.

That is interesting and new to me. If you are using an oiled filter like K&N then I doubt the current is high enough to burn off the oil.

It's not hard to remove and clean but you do have to be careful since it is not a cheap part and I doubt you can explain why it is broken to the dealer when it doesn't have any moving parts.

[charon]

Originally Posted by Beowoulf

That is interesting and new to me. If you are using an oiled filter like K&N then I doubt the current is high enough to burn off the oil.
.

Don't know how good it is at burning off oil, but I just looked it up to refresh my memory. BOSCH Automotive handbook starting page 471 states that there are 3 kinds of air flow metering systems, the hot wire, hot film and Karman Vortex Volumetric. From what I've seen of my M3 intake, it appears to be the hot wire.

The handbook states that the computer leaves the wire hot for 1 SECOND after shutdown for dirt to burn off. The Hot film air-mass sensor apparently does not need to be cleaned according to the book because the areas on the sensor element which are decisive for thermal transmission are at a downstream location to the air which prevents them from being affected by deposits on he sensor's leading edge. The Karman works via ultrasonics through the airflow and is therefore not prone to deposits.


Interesting stuff.