cold start problems - continued

[Huw Powell]

> I am still diagnosing my cold start problem on my 90.

What year 90?   What follows refers to 10v versions.

>  What controls the
> idle enrichment: as when the A/C is turned on, or during starting a cold
> engine and the idle is automatically raised to 1200 rpm for about two
> minutes or so.  Is it the ISV or a fuel enrichment.  Currently, the engine
> wants to idle at 900 rpm no matter hot or cold, before it used to bump the
> idle up during warm up.  Currently when I depress the pedal with a cold
> engine it shutters or simply stalls or when I depress it even more I hear a
> loud pop from the air box, and the rpm will climb.  More often than not I
> have to restart the car 4 times before it actually will idle without
> stalling.  What controls the idle in this beast?

I think you are chasing the wrong demon.  The idle is always supposed to
be the same, roughly.

If you can't get off idle when cold, you may be running lean, which may
be due to air leaks or an improperly set static fuel mixture, for instance.

The ISV controls the idle; fuel enrichment is used to make it run when
cold and to get slightly more power when the WOT switch is closed.

--
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/