Using XGauge you can add a MAF monitor into your scangauge's readings:

TXD 686AF10110 ;reads OBDII MAF
RXF 044145100000 ;the number 4 in the 5th position gives you two decimal
RXD 2810 ;specifies scangauge to read 2bytes (0 to 655.35)
MTH 000100010000 ; math is simple, multiply by 1, divide by 1, no adder

This returns MAF readings in grams/second.

I learned about this on the VW board and assume OBD is universal enough that it would work on the Mercedes too. For VWs there is a neat little trick there for "fooling" your MAF into thinking the EGR system is functioning when it is not. Basically all you need to do it twist the element in the housing until the reading at idle is low enough that the ECM thinks the EGR has opened and you won't get a CEL after plugging the vacuum line to the EGR valve. The rest of the MAF profile is more or less the same (it seems to actually cause the MAF to read slightly higher at higher RPMs too which is good). I'm guessing we could do a similar EGR bypass on the OM606 but you would need to know the value the ECM is looking for when it calls for EGR to open...but I thought I would post this here for all of you who have scangauge and like to experiment.

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz