Re: Control (Warm-up) Pressure Regulator Question.

[Huw Powell <audi@mediaone.net>]

Ti Kan wrote:
> 
> BADFISH469@aol.com writes:
> > 1) What year/model audi uses the Control Pressure Regulator (warm-up reg.)
> > with a port to the atmosphere, and a port to vaccum (so when the motor goes
> > to vacuum, or boost, however it is set-up, applies more pressure, to richen
> > the mixture) Also, I need the part number too so I can verify what i am
> > looking at.
> 
> Only Audi turbo models in in early 80s used the control pressure regulator
> with vacuum lines.  The specific part number varies from model to model
> (I guess different calibrations).

Not true; both 82 coupes I have had and the 80 and 81 5k's all had vac
lines to the CPR.  Two, in fact.

> 
> > 2) How do I set the vacuum port, to enrich my mixture at WOT (where the
> > vacuum is non-existant). Keep in mind, that I have a NON-Turbo 924, so I
> > never go on boost. TIA
> 
> The easiest way to do this is not to mess with the vacuum port at all.
> On the CIS cars with oxy sensor, there is a thermoswitch plumbed in the
> coolant line (usually in the path of the heater hoses) that is closed
> when the coolant is cold.  This tells the ECU to run in open-loop enriched
> mode.  When the coolant warms up, the switch opens to tell the ECU to go
> to closed loop operation.  You can wire up a full throttle switch on
> your throttle body in parallel to the OXS thermoswitch, so that when you
> floor it, will cause the ECU to go to enrich mode.  This is in fact how
> some of the early CIS cars with full-throttle switches are wired from
> the factory.

the later ones go open loop and to a higher, preset, frequency valve
duty cycle as well. (62% ?)

-- 
Huw Powell

http://www.humanspeakers.com/audi/

82 Audi Coupe; 84 4kq; 85 Coupe GT; 73 F250