Mass Air Flow sensor & Turbo [Archive] - Bimmerfest - BMW Forums

: Mass Air Flow sensor & Turbo

07-03-2007, 12:09 AM
Hi there!

In a 1995 325i there is the MAF sensor close to the Throttle body.
So, when we use a force induction such as turbo, where should this sensor be? In the intake of the turbine or the pressurized intake? If it has to be in the intake of the turbine, doesn't the prolongation of the cables of the sensor harmfull to the signal?


07-03-2007, 12:47 PM
Before the charged air.

07-07-2007, 05:17 AM
My turbo project car is a Nissan, but I think this stuff is essentially universal: MAF goes upstream of the turbo intake, yes. Also, ideally any BOV outlet should be rerouted back into the intake between the MAF and the compressor inlet, not just vented, as this is also metered air.

If you're concerned about lengthened wiring, you can substitute a larger gauge of stranded copper to minimize resistance. I found it advantageous to run a separate ground lead from MAF to chassis, as the stock harness had a 0.2 V drop. (This may not be an issue in your application--it was a TSB for my stock Nissan motor.)

07-08-2007, 11:10 PM
Now we are talking.

Nice tips... I will dor shure follow them. About the ground next to the sensor, thatīs a good idea. Bad ground is a real problem when it comes to sensors.

Thank you very much.