HELP! 2.1 idle woes..

[skysurfin09]

Help please anyone staying at home and on the computer tonight? May be it's a coincidence but after miserably trying to remove air from my rad, my bus has started to idle on warming up at approx 2500-3000 revs which is awfully uncool when trying to park or when sat at lights. I've read the Tech articles that are available and consulted my copy of Haynes but no help. I've checked the idle stabilisation valve and it is vibrating and I've unplugged the cable and I have a resistance measurement of 4.85 which is within the 0-10 guideline. The bus goes for it's MOT on Thursday and I really need to see if I can sort this before then. Any help would be much appreciated. Rob

p.s 2.1 digijet '89 WBX thanks

[mark]

if you search ''stabilisation'' you'll get all the info you need. try bypassing the idle stabilisation by joining the 2 connectors together. the same as when you check the timing. could also be the temp2 sensor failing and over fueling the engine when warm. or the old chestnut of cleaning all the electrical contacts with contact cleaner and a tooth brush this improves things no end and is a couple of hours well spent

mark

[skysurfin09]

Many thanks Mark for taking the time to reply. Typical I was feeding in any combination of idling or tickover not thinking of stabilisation. Rob

[skysurfin09]

I've just been checking the Tech regarding this problem and in reading realised that whereas normally I'd hear a buzzing from the idle control valve I now no longer hear this. It is recommended that it be removed and thoroughly cleaned , is this a straight forward operation as I'm dangerous with spanners? Rob

[icosahedron]

For the engine to rev like that it is getting a generous air supply from somewhere. Only three possibilities, idle control valve not working properly, throttle body valve stuck open or an air leak somewhere.

If the idle control valve is not working properly, the problem will more likely be with the control unit behind the offside rear light. Try pinching the pipe to the idle control valve with your fingers to cut off the air supply and see what happens.

Check that the throttle body butterfly valve closes properly and is not stuck open. Broken return spring, the butterfly could have worn into the side of the body or your accelerator cable is sticking.

An air leak means unmetered air, a very lean mix so watch out. Check all rubber pipes and seals for cracks etc. Don't forget the brake booster pipe.

You'll get it sorted.

[skysurfin09]

Ico, thanks for the tips mate I was beginning to think that everyone had gone to the moon. Trouble is I know just enough to be very dangerous around vehicles. Rob

[skysurfin09]

After much cleaning and fiddling I realised that the throttle cable was very taught as it comes into the engine bay. I took a gamble and released the tension on the cable and sure enough ...the revs dropped to the correct level.. In my defence I hadn't touched it before and therefore assumed wrongly that the fault didn't lie there... Thank you for your advice and guidence..Rob

ps. throttle cable was one of the very first bits of advice given...just shows