Volks,
I just spent the better part of the day diagnosing my fuel injection on my 81 and am back where i started.   

I have an official vw AFC book, as well.  What I do not get is the process when it is starting cold.....air flows thru the AFM, and if the motor is cold enough, the auxillary air regulator is open, and air is diverted to the intake manifold, thus bypassing the throttle body.  This book says that this enables the motor to act the same cold as it does hot, for the control unit adds additional fuel to the injectors when it senses the engine is cold.  Now, there is no sensor, or anything on the throttle body, so how does this auxillary air regulator do anything?  The air still ends up in the intake manifold and thus diverted to the cylinders anyway..................I could see it doing something if it were unregulated air, but it is regulated at the AFm.................

Adam P

81 Vanagon westy ( The Brick)
70 SingleCab "Whitey"
74 Beetle "ol yeller"
73 Transporter (STILL at paint shop)

Used Vanagon Parts for sale (mostly aircooled)