BMW 3 Series E46 - Mass airflow sensor

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Mon 8 Apr 2013 09:57
BMW 3 Series E46 - Mass airflow sensor - Peter vV

hi all.I have bought a 2001 BMW 320d.i am having some performance problems.the turbo does not boost at all before 4000/rpm and when it does boost it does not boost the way it should.i have a feeling it could be the mass airflow sensor.The car also give of a lot of black smoke as i accelirate.could the turbo be faulty or the sensor?

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Mon 8 Apr 2013 10:55
BMW 3 Series E46 - Mass airflow sensor - Peter.N.

You could try cleaning the sensor by spraying some volatile liquid on it, don't touch it though its very delicate, what you really need is the fault codes read.

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Mon 8 Apr 2013 12:36
BMW 3 Series E46 - Mass airflow sensor - Collos25

Have you removed the swirl flaps (if fitted) if they have not been removed I would suggest its your next job.As for the engine lacking boost I would take it to a BMW specialist these engines have so many sensors and have Vanos, with so many reasons for the engine not working properly any remote diagnosis is almost impossible.

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Tue 9 Apr 2013 12:16
BMW 3 Series E46 - Mass airflow sensor - BenG

Could there be a boost leak somewhere? Could account for black smoke (insufficient air / excess fuel) and lack of power? Would usually be accompanied by a hissing sound of pressurised air escaping.

Check all the pressure pipework between the turbo compressor and inlet for oily spatter marks.

If not then suggest gettting fault codes read as plenty of other possible causes, usually electronics...

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