I calibrated the air flow meter on my 190
Calibrating the air flow meter is not that hard at all, it just seems this way
all you need is a good multimeter and LOTS of patience.
Mine was glued on and I decided to rip it off and put it back the way it should be, why it was done this way I dont' know but it's fixed now
What I did is set it to it's lowest possible reading, this takes micrometer precision so make sure you got a steady hand.
also don't let it be too lose when you are adjusting it because the slightest movement will set it to some catastrophic value.
that's all there is to it really, worked for me at least.
stupid guy told me I would need the entire air flow meter asembly which is $800 or more
took me an hour to fix the problem.