Here's a video description of refurbishing a Bosch AFM for a Porsche 924S/944. On a wide open throttle run, it would go flat at ~2000 rpms before getting itself together up towards redline. This is a good thing to check if you're experiencing any kind of random hesitation and have ruled out the obvious stuff, like vacuum leaks, bad plugs/wires/distributor points, oxygen sensor, ect. This same repair concept probably applies to any other barn door-type AFM, only getting at the inner workings will be different. This info was mostly from www.the944.com under "Air-Flow Meter"
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