Daewoo Lanos high Idle speed

Hi,
My Daewoo Lanos is having a problem with its idle speed being too high. At a standstill it idles at about 1600rpm, and can be a bit embarassing
at the traffic lights. I have removed the idle control valve, given it a good clean, and it seems to be moving in and out ok when I switch on the ignition. I have also removed and checked all the various small bore pipes that go between the inlet manifold and a pair of plastic boxes attached to the bulkhead (gawd knows what they do !) but no luck, it still idles like I have the foot to the floor...
Any ideas anyone, I cannot afford to take it to a garage at the moment,
Paul...
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Is it warming up properly?
AFAIK, these have a separate wax stat which lifts idle speed independantly to the ISCV when the engine is cold.
Tim..
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There is a known fault on some Lanos that cause high idle and need an ECU software update. If you don't fancy paying Daewoo there is a temporary fix by:
Ignition On Disconnect Idle Speed Control Valve Ignition Off Re-connect Idle Speed Control valve Repeat 4 or 5 times Start Vehicle - It shouldn't idle unassisted so use the throttle. Keep vehicle idling on throttle to initialise self learn process It should now idle within parameters.
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Hi,
Thanks for the speedy responses. The engine warms up fine, but even when cold the idle seems faster than I would expect. Any idea where the wax stat would be ?
I will try the temp fix, and let you know if sucessful or not... fingers crossed,
Paul...
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Yes, on the inlet manifold. It acts directly on a supplimental air passage on the manifold. (rather than mechanically on the throttle linkage)
Tim..
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Fantastic, the unplug ICV + ignition on/off trick worked !! Thanks ever so much for your help, now happily idling at about 800rpm.. I no longer sound like a boy racer ;-)
Paul...
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Yes that seems to do the trick on these motors. Just repeat if the problem re-occurs. Another annoying problem I found on the Lanos is that when the car is rolling forward the speed sensor increases the revs to about 1300rpm but sometimes (especially if in heavy stop-go traffic) when the vehicle comes to a halt the revs don't always drop, but if you edge forward a couple of feet and stop again they will drop to normal.
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