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Re: Ur-Q Parts & Questions

	On the computer frequency valve output I can be more help. On my '83 when I 
	bought the car a previous owner who had  exactly the same problem you 
	described "fixed" the problem by connecting the frequency valve directly to 
	a 12V (switched by the ignition) supply. Hey 100% duty cycle, I discovered 
	this "modification" when the frequency control valve went super nova. 

	As an interim solution I connected a couple of high power resistors to drop 
	the voltage down to 6 volts. On closer inspection of the ECU, I discovered 
	the original cause of the problem. A PCB trace from the large transistor 
	that drives the frequency valve was burned out. This is not surprising 
	since the frequency valve draws 2amps and the PCB traces are not 
	particularly wide, given time and a bit of electromigration and hey you've 
	got a fuse. (RDH insert comments on quality German electronics here!)

Weeelllllll, I will comment that the ECU is actually made by Hitachi . . .
albeit apparently to "Audi" specs . . .

	Anyway the moral is remove the ECU and examine the PCB carefully. It could 
	also be the connector to the ECU from the wiring loom.

Or a zillion other varied and sundry connectors strategically scattered
throughout the wiring harness!