Idle speed

[FFMan]

The idle on my recently acquired Griff seems a little erratic - varying between 900rpm and 1500 for no apparent reason.

Does this setup have an idle speed control valve (ISCV) like my old 4x4 sierra used to or should I be looking somewhere else ?

thanks

[Ozstyle]

Hi,
idle speed controlled by the ecu via the stepper motor. Remove stepper motor from back of plenum and give it and its housing a good clean. Search forum there are plenty of threads on this if you need more advice.

Ozstyle

[steve-v8s]

Perhaps should add that it is normal for the idle speed to remain high when first coming to a halt. After a few seconds the ECU will reduce the idle speed in two distinct steps to the normal level. Having said that the Stepper valve does tend to get gummed up and is easy to clean.

[FFMan]

oh ok - that's interesting, because this is what appears to happen but i interpreted this as erratic rather than by design.

I noticed I was crusing along came to a stop and the idle was 1500, then appeared to drop to 1100, then 900 over the coruse of i guess 15 secs or so.

Are you saying this is OK and by design ?

[steve-v8s]

That's what mine does, see what others say. They will be along soon....

[That Daddy]

yep give or take a few seconds,thats what its supposed to do.

[derbygreg]

or take out the Stepper motor if you dont like it and blank it off... may mean you have to use a little throttle just after you start it on a cold morning...