My understanding is that over time, the AFM wiper wears the resistive
strip at idle or cruise "positions". Much like a dirty volume control
on a radio, there can be voltage drop outs at these positions so the
AFM ends up sending "dirty" signals to the ECU. Your '81 engine
management is obviously different (and simpler) than that used on the
1.9 and 2.1 so the ECU may not get affected by the same AFM wear
issues.

Bentley shows test procedures for the AFM but this test:

http://www.thesamba.com/vw/forum/viewtopic.php?t=369815&highlight=afm+voltage+test

is pretty useful and might be possible on the L-jet system (air
cooled). One would obviously have to be certain of which probe goes to
which wire on AFM connector.

Neil.

On 11/17/14, David Parsons <bugnut1@comcast.net> wrote:
> Is VANAGON syndrome only related to 86-91 vanagons? I have an 81 that sure
> acts up like this syndrome is described.
>
> Sent from my iPhone

--
Neil n

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