Airflow Meter (AFM) check

[wildejon 7]

I really hate to ask this as I know it's here somewhere but I can't find it.

I have an issue where my oil is changing colour/going very dark and smells burned. 
One thought we had was that the AFM might be worn and screwing up the mixture. 

How do I test it though? I tried off the car, measuring the resistance as the flap moves (which doesn't give a smooth reading at the top end) but I also found an article that said to test it with a supply/on the car.
Might someone guide me or point me to a known good guide?

[PhilNW 44]

got this one

 

http://www.clarks-garage.com/shop-manual/elect-22.htm

 

Edited January 7, 2021 by PhilNW

[wildejon 7]

Ah, nice one, thanks!