1984 4k - no start quattro (Now - runs, but not perfect)

[Tony Hoffman]

Glad to hear you got it running. The O2 connector is two seperate
parts. One has two wires, the other has the signal wire. The signal
wire is green till it gets to the black wire of the O2 itself. The
connector is usually lying right under or around the distributor by
the bellhousing. The other two wires going to the O2 are for the
heater in it. One is power the other is ground.

If you are getting more than 1V from the black/green wire you probably
have a shorted O2. If not, it should be good. Although, it can be in
spec and still be slow reacting. However, in these older CIS cars, the
O2 has a pretty small range of adjustment when compared to the newer
cars. I believe it's somewhere in the range of 5% either side of the
basic adjustments.

Tony

On Sun, Sep 27, 2009 at 11:38 AM,  <vittorio at mybares.com> wrote:
> Well, if nothing else, the car is getting a lot of sorely needed TLC :)
>
> The no-start problem seems to have been fixed (I haven't had a no start
> in the last 3-4 days). I believe it was due to:
> a) a bad connector going to the ignition control module - or possibly the
> ICM its self.
> b) a broken o-ring in the differential pressure regulator
>
> Idle control valve got a good clean and lube - Idle is much more stable.
>
> Valve cover gasket was replaced as it was leaking - my local parts supplier
> had one in stock for $2.57 - one they must of had on the shelf for many
> years, it is made out of cork just like the original :o I don't know the
> last time I've seen a cork gasket. Anyway - don't know if its good bad or
> indifferent, but figuring it was a bit dry from sitting around for a long
> time, I smeared clean motor oil on both sides before installing it. Torqued
> down the nuts to 7ftlbs. Seems to be holding well so far. Valve cover also
> got sandblasted and some paint.
>
> Replaced 8-10 small vacuum hoses.
>
> Still seems to be low on power (just slightly mind you) and if you blip the
> throttle from idle it mildly stumbles - as it it wasn't on all cylinders.
>
> Next item to check was the 02 sensor - looking at my haynes - says theres a
> plug that can be used to check in the engine bay. I found a 2 prong female
> plug just next to the battery with 3 wires going to it. If this is the
> correct place to check the 02, I'd say its toast as it reads a constant
> 10.89V...am I reading the right plug?
>
> TIA
>
> Vittorio -