Re: Frequency Valve

[Huw Powell <human@nh.ultranet.com>]

> Actually this is an early 1984 with the mechanical fuel injection and the
> 2.1 L engine.  Too bad for me!

It's ok, they're not *that* baad!

Your freq valve should be buzzing all the time, as I said, the ECU
controls it with feedback from the OXS.  Pic of where to test the duty
cycle at the url below.

possible failure modes (I'm sure there are more...) include ECU grounds
(by coil on firewall I think), wiring to FV, FV itself, etc.

The FV should have 12v constant at one side (same circuit as fuel pump)
and the other side is grounded intermittently (like 50% of the time + or
-, at about 15 Hz) by the ECU.

Hope this gets you started...

-- 
Huw Powell

http://www.thebook.com/human-speakers/audi-timing.htm

the steering wheel isn't connected to anything, it's just a place to
rest your hands