Audi 100 Won't Start: Breakthrough

[Edward R. Wendell IV]

Ok, I'm assuming that this is a NF code 130hp engine. The reason I ask 
is that I only have the 84-88 Bentley but I'm under the impression that 
the engine in the 100 is the same as the 87-88 5000 with the NF engine..

  What you have been referring to as a thermo time switch isn't, at 
least not when compared to the real thing on the early 80's CIS (K 
jetronic) system. On your system CIS-E III (KE jetronic) the sensor on 
the top of the water outlet is a dual NTC thermistor sensor. It's two 
sensors in one housing. Pin #1 to ground supplies temp info for the 
knock sensor control unit and pin #2 to ground supplies temp info to 
the injection control unit. The reason that I point this out is that 
I'm under the impression that you connected a resistor across the two 
terminals on the connector. What you should be doing is connecting the 
resistor between terminal #2 and ground. What gave me this idea is that 
you measured 3.5k ohms on what you have been calling a thermo time 
switch. Measured correctly (between either pin and ground) the most you 
should have gotten was 2.5k ohms.

Not that this really matters. As you found out, your problem is not 
with the cold start system, it's elsewhere. I'm just trying to 
eliminate the mystery of the cold start system that doesn't respond to 
temperature.