"So the $1,000 air flow meter never goes bad? Isn't the AFM different from the potentiometer?"

Actually, the potentiometer is the one that goes bad in the AFM.
(the pot is part of the AFM)
In the past you had to buy the whole thing (1k bucks), now you can purchase the pot separately (for 40 bucks plus shipping), and attach it to your AFM assembly.

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1999 Porsche 996 Carrera Convertible
1994 420E - SOLD
1986 300E - SOLD, what a car
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