I would take the risk of installing the pot myself ($42), rather than pay $1K for the whole unit "to see if it fixes the problem".

By your description the techs are just throwing parts at the problem, with no success.
New wires (3 times), new fuel pumps, new coil, new fuel filter, now new AFM?
Proffesional mechanics are supposed to diagnose and repair, not throw parts at it at your expense.

You and I can do stuff like that.

If you do not feel comfortable changing the pot, perhaps we can meet a weekend and work on our cars together (may be 87-300E_in_NC will join us, his mechanical skills are excellent). He has a spare pot, which we can test. Or may be swap pots from our cars.

Just let me know.

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