On 12/7/05, TC <trclark@shaw.ca> wrote:
>
> http://www.bostig.com/products/
> Luftmassenmesser Umr�stsatz (LMU)  COMING SOON!

Ah, the "air mass meter over-conversion kit". Presumably the hot-wire unit
with a microcontroller "interpreter" for the ECU that was alluded to some
time ago.

ok so how come no one has made this better mouse trap b4

Probably because it's a bit of a pain collecting the conversion factors.
Converting the variable-voltage output of a hot-wire AFM to the
variable-resistance output the Bosch ECU expects is probably the easy part.
Mapping out what voltage equals what resistance sounds like a big pain in
the butt, particularly because the voltage output of the hot-wire is
affected not just by the amount of air flow, but also by the temperature of
the air. ECU's designed for hot-wire AFMs compensate based on the air temp
sensor. Since the Bosch ECUs in Vanagonsdon't do that, the interface device
probably has to account for that as well. All I can say is, better them than
me!

Neat overview of electronic AFMs here:
<http://www.autoshop101.com/forms/h34.pdf>
They even explain the Karmen Vortex type sensor! Neat.

--
John Bange
'90 Vanagon - "Geldsauger"