From what I was able to learn at the fantastic MAF tech session at this year's Frenzy 7, K&N seems to be a common culprit in accelerating the death of our MAF's. Speaker Jon Holdsworth's explanation of the MAF is that the platinum wire sensor goes through a quick burn cycle at every engine shutdown. The thin MAF wire gets a high voltage kick to burn off any residue. Eventually the MAF wire will get so thin that resistance will fall outside the compensation range of the LH box. (I think that's the computer responsible) A well lubed K&N filter will deposit K&N oil on the MAF sensor wire and cause more of the wire to burn off at each shutdown. Someone mentioned that a carefully oiled K&N with oil application only on the top side of the filter may prevent this accelerated MAF deterioration.
Common consensus is to ditch the K&N and use the good ole paper filter.
Hope I got most of the salient facts straight.
> I bought a used 89 928 and the MAF crapped out on me, and it does
>have a k&n filter. Should I chuck the filter in the trash?
0 280 214 001 Air Mass Sensor Superseded by: 0 986 280 124
0 986 280 124 Air Mass Sensor Supersedes: 0 280 214 001 Remanufactured Part
BMW 13 62 1 311 950
BMW 13 62 1 715 888
PORSCHE 928 606 141
PORSCHE 928 606 141 00
VW 035 133 471 AC