efi&mpg readout possible?

[Marc Swanson]

> Another question came up with repsect to my planned efi conversion on
> my 200q. What would happen to the mpg readout?


that is generated via a signal from the potentiometer on the CIS flow
plate.  Thus when converting to EFI you loose the readout.

On 034EFI, there is a wire that sort of simulates the potentiometer
output that is mostly for use in fooling the ignition computer into
supplying the appropriate spark advance based on load.  I didn't hook
this wire up to the trip computer on my 4ktq (I'm running the type 89
ignition system) but Nate did on his 90tq and the MPG readout is kind of
funny to watch, nowhere near accurate.  It usually reads about 80mpg
while cruising if I remember right.  If you _really_ want to get a more
accurate reading you'd have to get real creative and design some kind of
circuit that would take in things like the map signal, intake
temperature, etc and calculate the MPG using the engines volumetric
efficiency as part of the equation and then producing a signal that
would replicate the output of the potentiometer.  In my mind, nowhere
even near worth the effort :-)

--
-Marc
87' 4ktq
88' 90q
www.mswanson.com/audi