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        General >> Problems >> Still troubled with poor idle
        
(Message started by: Mike_Floutier on Dec 21^st, 2007, 2:37pm)

Title: Still troubled with poor idle
Post by Mike_Floutier on Dec 21^st, 2007, 2:37pm

Hi all,

Still haven't got to the bottom of my poor idling (hunting rather than mis-firing imho).

Firstly, many thanks to Highlander for the 2.0 IACV - just for the record it does fit the 2.3 and it does work exactly the same as my existing one so that might be useful for someone in the future.

Anyway, back to the continuing idle problem. I've tried disconnecting the coil packs one at a time but there's no difference so I've ruled them out. Also I've replaced the HT leads as they had given trouble in the past. I've also replaced the plugs but again no change.

Oh, I should also mention that the hunting idle gets progressive less by: 1. engaging drive, 2. turning on the air-con, 3. turning on the heated screens etc

So, what am I left with?

1. I understand that a leaking inlet manifold will cause poor idling but I'm not sure how to test for this - could someone tell me please???

2. Also, I recall seeing something about "a loose hose on the EVAP canister causing poor idling - is this right, and if so would it apply when I'm operating on lpg?

Thanks for you help with this, I do need to sort it out as it's potentially embarrassing for a private hire driver - although I have been able to hide it by judicious of aircon etc and keeping my foot lightly on the throttle at traffic light etc.

Mike

Ps Have a great Christmas everyone!

Title: Re: Still troubled with poor idle
Post by Tons_of_fun on Dec 21^st, 2007, 4:13pm

An old fashioned way of checking for inlet leaks is to spray a little WD40 or similar around the area you suspect to be leaking (whilst engine is running).If the revs increase you have found your leak.Must stress though this is a very old fashioned method used on old cars but i would of thought the same idea applies.Unless anyone knows different ???

Title: Re: Still troubled with poor idle
Post by Simmo on Jan 5^th, 2008, 6:38am

Certainly I have seen this method work on 'our' cars. One of our members used carb cleaner for the same effect, and it certainly 'affected' the performance.

Title: Re: Still troubled with poor idle
Post by TiberiuS on Jan 5^th, 2008, 5:25pm

I used unlit propane torch on mine, after all it's all fuel to the engine and burns quite nicely. But for obvious ('Elf and safety) reasons I wouldn't recommend you do this although it works great for finding cracked inlet hoses etc. Small amount of excess (unmetered) air will make the engine race above idle speed, any more and it'll start to run lumpy and eventually lean out to the point where it just dies because the ECU can't adjust the mixture for all the air the TPS and MAF isn't 'seeing'

Could also be an injector solenoid coil breaking down, it would affect the ability of the injector to open for really short pulses (like at idle). But again it's a stab in the dark, you might buy another set of injectors and just have the same issue :-/

Title: Re: Still troubled with poor idle
Post by mindofitsown on Jan 7^th, 2008, 8:04am

Some interesting tips on the subject. I have used fresh engine oil and watched excess smoke pour out of exhaust.