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164.122--642.940 CDI B2/7 Hot film mass airflow (value above limits)

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164.122--642.940 CDI B2/7 Hot film mass airflow (value above limits)

New HFMAF installed, new EGR installed, Code cleared 10 times!

Wiring rings out to N3/9 ECM .2 .3 ohms on all leads

Both B2/6 and B2/7 read normal running and read normal engine stopped, but N3/9 throws HFMAF sensor (value above limit) immediately after start, but shows normal when read! Raw value is suppose to be between 200-450 us and it returns 487 us

Also, after readapting both MAF and EGR while running, no new code until restart and then, instantly shows 1 event.

642 150 61 79 ECU is installed.
642 090 82 37 MAF is installed

The ECM computer was superseded 4 times in 18 months by MB up to 2/2008.

642 150 61 79 Earliest, just like mine
642 150 23 77
642 150 97 78
642 150 54 41 Last update from February 12,2008

What would waldo do???
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WAG here, but the old MAF read OK?

Does a high reading suggest not enough air passing the MAF? Leaks maybe?

How many miles on truck? Drivability OK?

What led you to replace the ECM and MAF?

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