Measuring resistance of air flow meter

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spacechimp
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Post Wed Dec 19, 2012 5:31 pm

Hi,
What resistance should the variable resister be in the air flow meter of a 316i m40, 1989 E30
:mad:
Speedtouch
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Post Wed Dec 19, 2012 5:38 pm

///M aurice
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
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Brianmoooore
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Post Wed Dec 19, 2012 6:57 pm

You cannot reliably test an AFM by making resistance measurements!
The correct way to test one is to connect a six or nine volt battery across the outer terminals of the potentiometer, and then monitor the voltage on the wiper while carefully opening the flap by hand, preferably with an analogue meter. There should be no sudden jumps in the meter needle, and most importantly, the voltage should not drop at any point.
soul4t
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Post Wed Dec 19, 2012 11:17 pm

As Brian said, I performed the test on the AFM in the car with mine, with the top off the AFM. The ECU supplies 5v AFAIK, so it can be measured as Brian suggests! What problems are you experiencing with your car?