86 4kq idling at 2500RPM

[Huw Powell]

> The bad news is that it now idles at 2500RPM. If I blip it, it comes back
> down to 1300 or so, hovers unevenly + or - 300RPM, then shoots back up to
> 2500 ish.

Seconding Ben Swann, I would first check whether the idle switch is
closing when the throttle is "off".  Without it, the ECU does not know
the engine is idling and does nothing to control the rpms.

> If I unplug the ISV, nothing changes.
>
> Same with CSV.
>
> The idle air bypass screw on the side of the intake is screwed in all the
> way.
>
> The throttle linkage is not stuck.
>
> If I unplug the DPR, then the car drops to an unsteady, unhappy idle of
> around 800RPM.
>

--
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/