Ignition trouble shooting on Eurovan - Audi related

[Ben Swann]

I have a '93 Eurovan with 5 cyl. - just died one day.  Ignition related and I've
confirmed weak or no spark from coil.  I rewired it to fit an audi coil with Darlington
transistor - similar, but uses a larger plug, but same three wires.  Figures VW used a
different combination/connector, but for all intent and purpose looks like just a
variation on the theme.

So after testing the Eurovan coil for spark and getting a weak spark then rewire and
substitute the Audi coil  - Now I find zero spark on the AUDI coil assembly  - I at
least saw a weak spark on the VW one, so trying to see if I need to revert or I can use
one of these  ones that I have  a half dozen or so.  

Here is the question - What is the switching voltage on the center pin (2) usually green
with whte stripe wire and comes off the ECU?

I'm being a little vague here because the same coil setup - darlington transistor
adjacent to coil with 3 pin connector is used on several of the AUDI models including
200Q20V, Coupe Quattro and late 200 (MAC-14) as well as 100 with NF engine and others,
so the pin on the ECU may change, between ECUs.  On '90 model 80 it is pin 11 on the ECU
and on '90 Coupe Quattro is pin 9A.  MAC-11 on 5000tq uses a 2 pin connection, so not
working with that one.

Anyway I'm 

(1) trying to test some coils to see if they are good and with +12V on pin 1 of
connector and  pin 3 to ground  - what is min.  voltage  required to trigger the coil?  

And (2) trying to see what Voltage I am getting out of the Eurovan ECU if possible/ and
what voltage is should be putting out in case I need to amplify the input voltage a
little - I'd like to stick with the AUDI coils since I have plenty of them and the VQ
one looks like it was designed for planned obsolescence - I digress.

I know I ought to test Hall output, but difficult on this vehicle so may be going in a
roundabout way - I presume if I was getting any spark from the ECU on the Eurovan, then
hall signal was present anyway.

Ben

"Basic research is what I'm doing when I don't know what I'm doing"  Playing with
flashlight battery and coil combinations in the garage while holding one end of spark
plug in my left hand =0