Erratic idle

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Tue 30 Jul 2019 22:11
Erratic idle - Lee Griffiths
Hi

My Mondeo is suffering from an occasional erratic idle which is baffling me and I hope someone can assist.

Every now and then the revs will continually jump up and down, sometimes cutting out completely.

If I restart the engine to issue goes every time also when I rev the end hard it seems to sort it for a while.

I have replaced the purge valve and also cleaned out the EGR valve and at a loss what to do next.

I want to sell the car not incur more money on it, any advice welcome!!


Thanks
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Wed 31 Jul 2019 00:03
Erratic idle - elekie&a/c doctor

Not much info to work on here. Age ,,engine size, petrol, diesel, auto, manual trans.?????

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Wed 31 Jul 2019 00:48
Erratic idle - Lee Griffiths
2006, 1.8 lx 16v, petrol, manual.

Cheers
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Wed 31 Jul 2019 09:13
Erratic idle - elekie&a/c doctor
I would start by cleaning the throttle intake and butterfly flap. Also remove and clean the idle control valve. Both easy jobs. You may have a split or collapsed engine breather hose . This needs the inlet manifold removed for access.
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Wed 31 Jul 2019 12:48
Erratic idle - Lee Griffiths
Thanks I have cleaned the throttle body and butterfly flap. Took off and cleaned with carb cleaner.

Is the idle control valve separate to the EGR valve?

What confuses me is if I turn the engine off and on it solves the issue.
If there was a split hose would there not be a constant issue?

I replaced the PCV valve about two years ago that was hell of a job!

Thanks

Edited by Lee Griffiths on 31/07/2019 at 12:49

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Wed 31 Jul 2019 18:28
Erratic idle - elekie&a/c doctor
The egr valve sits on the top of the engine, next to coil pack . Idle control valve is bolted to the side of the throttle body. I would also check the engine Ecu memory fuse in the engine bay fuse box . If I recall , it’s a 3 amp purple colour .
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Wed 31 Jul 2019 20:22
Erratic idle - Lee Griffiths
I did remove the idle control valve when I cleaned the throttle body. I’ll check the fuse as haven’t done so.

It is very frustrating to pinpoint..

Thanks
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