[Diy_efi] Air Flow Meters

[Phil Lamovie]

Our Good friends at Bosch have five Mass Flow meters that are
0-5 volt. Not exactly linear but very doable with an A/D and
a look up table

Starting at approx. ~150 hp and getting up to 450 hp or so.

I have seen them in print and considered them for a project I was working on.

I don't know if they have ever been used in an OE installation.

Hit google with the query  Hot-film air-mass meter, Type HFM 5
or use the part numbers below.

Measurement of air-mass throughflow up to 1000 kg/h

HTH

Phil


The following table can be reassembled if you tab it.

Output voltage UA = f(Qm) of the air-mass meter
Part number 0 280 217 123 0 280 218 019 0 280 217 531 0 280 218 008 0 280 002
421
Characteristic curve1 2 3 4 5
Qm/kg/h UA/V UA/V UA/V UA/V UA/V
1118 1.4837 1.2390 ? ? ?
1110 1.5819 1.3644 1.2695 ? ?
1115 1.7898 1.5241 1.4060 1.3395 1.2315
1130 2.2739 1.8748 1.7100 1.6251 1.4758
1160 2.8868 2.3710 2.1563 2.0109 1.8310
1120 3.6255 2.9998 2.7522 2.5564 2.3074
1250 4.4727 3.7494 3.5070 3.2655 2.9212
1370 4.9406 4.1695 3.9393 3.6717 3.2874
1480 ? 4.4578 4.2349 3.9490 3.5461
1640 ? ? 4.5669 4.2600 3.8432
1850 ? ? ? 4.5727 4.1499
1000 ? ? ? ? 4.3312