Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: alexw80 on 30 July 2011, 14:23:43
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Sorry if it's a silly one, but just wanted to check.
I've done the paper clip trick on my P reg 2ltr cdx as described in another thread. As soon as I turn the key onto the electrics the engine light flickers briefly then goes out, but comes back on again as soon as I remove the paper clip. I'm assuming this is normal and the fact the light stays off until I remove the clip means there are no stored error codes?
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I believe so. However most of my experience is with later cars, so see what others say.
Was there an issue that made you look though...?
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I replaced the 2 breather pipes, cleaned out the IACV and breather jet, replaced the throttle body gasket and IACV gasket. But she idle hunts now. Bouncing between 1k and 2k on the rev gauge. Was hoping a sensor or something would have thrown up a code so I knew what was causing it.
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How did you clean the idle control valve? The symptoms are those of a sticking IACV.
When I cleaned mine I just squirted lots of carburetor cleaner into it. I have read that the internals a fragile and don't like being poked with a screwdriver.
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Carb cleaner and cotton buds. Is there any way to check to see if it's the IACV?
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Sorry, I didn't comment on your initial query.
Paperclip test: I thought that all cars that responded to the paperclip would flash 1-2 repeatedly if there were no errors (or 1-2 three times followed by the error codes) paperclip test and pedal trick (http://www.omegaowners.com/forum/YaBB.pl?num=1189022687)
As to testing the IACV I think everything can be tested using Tech II. You just need to get yourself to someone with Tech II.
Where are you? Update your profile with your location and you will probably get offers of help or directions to the nearest Tech II expert. :y
[edit]The guide to the paperclip test does say that later 2.0l ecu's use a 4 digit code and don't bother with the 1-2[/edit]
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Thought I'd already added location, done now lol
So I'm guessing a P reg would be classed as a later 2.0 then?
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I replaced the 2 breather pipes, cleaned out the IACV and breather jet, replaced the throttle body gasket and IACV gasket. But she idle hunts now. Bouncing between 1k and 2k on the rev gauge. Was hoping a sensor or something would have thrown up a code so I knew what was causing it.
Air leak
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I replaced the 2 breather pipes, cleaned out the IACV and breather jet, replaced the throttle body gasket and IACV gasket. But she idle hunts now. Bouncing between 1k and 2k on the rev gauge. Was hoping a sensor or something would have thrown up a code so I knew what was causing it.
Air leak
Did it do it before you had it apart?
If it didn't then it is 99.9% certain that it is caused by something you did.
Are there any other symptoms?
I have never had an issue with an IACV but I have caused faults by forgetting to reconnect electrical connectors :-[
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Yes, perhaps not as much, but then I never let it tick over to find out before. That's why I stripped it all off to clean it. Fast running and very poor idling. I've noticed it running a little warm since it started idling rough, assumed that was probably due to me fighting the engine to slow down lol
It seemed to run a little rough when I first started it up after the clean out, but didn't hunt. Once it got warm it really started though
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Yes, perhaps not as much, but then I never let it tick over to find out before. That's why I stripped it all off to clean it. Fast running and very poor idling. I've noticed it running a little warm since it started idling rough, assumed that was probably due to me fighting the engine to slow down lol
It seemed to run a little rough when I first started it up after the clean out, but didn't hunt. Once it got warm it really started though
That does sound more like an air leak.
Does it drive OK otherwise? An air leak would result in the engine getting more air than the ECU intended (or was being measured by the MAF) which would make it idle fast and lean (which probably wouldn't be noticeable during warm up). It probably wouldn't affect normal driving.
I suppose a faulty MAF could confuse the ECU but I think that would probably upset normal driving too.
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The actual driving is quite smooth. It's only when I start to slow down I find it's running fast. The change down can happen with a bit of a thud sometimes as it's running faster than it should be for the change.
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Won't comment on the idling as I don't know, but as a reference (mine is v reg 2.0 CDX / X20XEV engine), when I did the paperclip test I got exactly the same as you, i.e. light went out shortly after putting ignition on then just stayed out.
I have had it on a tech2 since then and have been told there are no error codes showing.
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I suppose you have already read these guides
How To Clean Your 2.0L IACV and Breather Jet (http://www.omegaowners.com/forum/YaBB.pl?num=1194007453)
Cleaning the throttle valve assembly Omega 2.0 16V (http://www.omegaowners.com/forum/YaBB.pl?num=1207387811)
Cleaning X20XEV Idle Control Valve (http://www.omegaowners.com/forum/YaBB.pl?num=1152787761)
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My Focus has an air leak...I know where roughly just cant be bothered to get round to sorting it as its getting 40mpg anyway...but the symptoms are the same...its over revving when you take your foot off the accelerator, doesnt drop revvs the way it should as quikly as it should...I would look for an air leak...
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There do seem to be a lot of vacuum connections below the throttle body. Any one of those could let in enough air to cause a fast idle.
(http://images.omegaowners.com/images/guides/Throttle_Body_Assembly_2.0_16v_X20XEV/slika_40.jpg)
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Won't comment on the idling as I don't know, but as a reference (mine is v reg 2.0 CDX / X20XEV engine), when I did the paperclip test I got exactly the same as you, i.e. light went out shortly after putting ignition on then just stayed out.
I have had it on a tech2 since then and have been told there are no error codes showing.
Sounds like there's nothing stored on mine then. Thanks for the info
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I suppose you have already read these guides
How To Clean Your 2.0L IACV and Breather Jet (http://www.omegaowners.com/forum/YaBB.pl?num=1194007453)
Cleaning the throttle valve assembly Omega 2.0 16V (http://www.omegaowners.com/forum/YaBB.pl?num=1207387811)
Cleaning X20XEV Idle Control Valve (http://www.omegaowners.com/forum/YaBB.pl?num=1152787761)
Yes, they helped a lot. Don't think I'd have tried it without those guides. Although, still not done the large hose at the back on passenger side of engine yet.
I'll have another once over tomorrow to see if I can see/hear any air leaks in the pipes. Don't suppose anyone has any ideas as to the most likely place it could be?
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If you have some carb cleaner, I would try spraying that around the vacuum pipes etc. If you have air being sucked in, it will draw in the carb cleaner and you will hear a noticable change in the engine.
What ever pipe etc. you were spraying is the area for the leak.
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Had a good look and feel round today, can't find an air leak. So thought I'd check the connectors. Took MAF connection off while the engine was running and it dropped to a low rev but very rough, almost to the point of it cutting out. So assuming the MAF is working fine. Went onto the IACV connection, engine was hunting between 1k-2k, took the connector off and the car hit just under 2k and stayed there, no hunting. Re-attached it and she started hunting again. Sticky IACV?
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I would expect a sticky idle control valve to alternate between too fast idle and too slow idle (maybe even stalling).
It might be worth another look at the cleaning of the valve though because it appears to use a 'balanced port' design. Two valves on the same actuator shaft, one gets pulled open by the manifold vacuum, the other gets pulled closed. If the hidden passage in the valve body is blocked it might be causing the manifold vacuum to pull the valve open :-/
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Not sure what this implies for you, but I just tried disconnecting the (electric connector of the) IACV on ours while running and it cuts out very shortly afterwards. I couldn't be bothered to let the engine warm up fully from cold, but I'd expect the same TBH.
This makes sense to me, throttle closed, and no power to open the IACV so it too is closed; no air into engine >> stop.
I guess this does suggest that your IACV isn't closing correctly.
I picked up an ebay one for £30-odd when ours was on the blink, and 3+ years later it's still going strong. Worth a punt I think, if another clean doesn't help.
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Well, stripped it off again and gave it a thorough soaking this time. Put it all back together again, and nothing has changed.
Stumped. Got a mate who's a mech, will see if I can get hold of another IACV to try it and see if that works. If not, a trip to my local garage may be in order. Unless anyone can sujest anything else?
Oh for the days when I could get by with just using a push bike lol
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If you can get it on a code reader that shows live readings you should be able to see if the ECU is trying to close the IACV or if it is holding it open for some reason.
If it is trying to close it then you are back to checking for air leak or faulty IACV.
If it is holding it open then check the sensors for duff readings.
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symptoms suggest air/vac leak.
96 on, 2.0l use 4 digit code, so no 1-2 start of sequence.
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symptoms suggest air/vac leak.
96 on, 2.0l use 4 digit code, so no 1-2 start of sequence.
Cheers for that, didn't know which code sequence mine used.
Fingers crossed I've got a mate of mine sorting out another IACV for me to try. If it works I'll get one. If not, searching for leaks again.
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Replaced the IACV with one from the local friendly breakers. £10, works like a dream. Just a slight blip from time to time on tick over, possibly needs plugs changed as I think the rocker cover gasket has gone. Idles just under 1k, no hunting what so ever. :D
Now just need to clean out the pipe at the back end of the engine, passenger side. I'll do that when I do the rocker gasket.
What's the best way clean the pipe? Take it off and drown it in carb cleaner or better to use something else?
Thanks for the help guys. Much appreciated.