hunting idle on 5ktq

[Huw Powell]

> I have a problem, the idle speed rapidly varies from 1200 - 1400 rpm and
> repeats about 1 time per second on my 1987 5ktq.

>
> The car drives great once gas is pressed, but when idle switch closes the
> problem persists.  Anyone have ideas about this?  The thing that baffles me
> most is that unhooking the ISV does not settle the idle down, which
> eliminates the control relay and wiring in my thoughts.

If unplugging the ISV changes nothing, then the ISV system is not doing
its job, I think.  Is there a test point on the 5kt to measure the ISV
duty cycle?  Examine the ECU grounds, which should be somewhere on the
intake manifold, as well.

--
Huw Powell

http://www.humanspeakers.com/

http://www.humanthoughts.org/