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Old Mar 13, 2008 | 10:17 PM
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When my 1985 goes into closed loop it won't idle. The idle will surge up to 800 or 900 rpm then drop off almost to stall at 300 or 400 rpm. happens alot in stop and go traffic. any suggestions???
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Old Mar 13, 2008 | 11:14 PM
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I would start with re-setting min idle and TPS. Did this come out of nowhere ??
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Old Mar 14, 2008 | 09:17 AM
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Vacume leak
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Old Mar 14, 2008 | 02:41 PM
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have done that .54 volts and don't hear any leaks???
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Old Mar 15, 2008 | 06:54 AM
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Supply some more info for us. The two suggestions are the usual for unstable idle.
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Old Mar 15, 2008 | 03:04 PM
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have you checked the IAC valve? could be a sign thats its beginning to wear out or build up dirt, debris, etc.
Last edited by PurtyLilC4; Mar 15, 2008 at 03:07 PM.
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Old Mar 17, 2008 | 08:45 PM
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Will be checking the IAC today..
info 383 stroker 282/272 cam tune port with world 2.02 heads,headers running 8 degrees timing with a standard trans.
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Old Mar 17, 2008 | 11:08 PM
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Originally Posted by AGENT 86
Did this come out of nowhere ??
Did this problem come out of nowhere, or is this a new combo ??
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Old Mar 17, 2008 | 11:52 PM
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Default EGR exhaust gas recycle
Could be EGR valve in intake,(this valve controls idle)possibly has debris in it.
Expensive to replace, buy some GM intake cleaner (spray bomb)and follow instructions to the letter.
I just did this on my 4.3 vortec(same symptoms) and it has never run so good.Took about 30 minutes.
You've only got 10-12 bucks to lose and if it doesn't solve it the improved mileage is payback aftera coupla tanks.
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Old Mar 18, 2008 | 08:51 PM
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Did the IAC, and it is still doing it. will try the cleaner. And yes it came out of no where about two weeks ago..
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Old Mar 18, 2008 | 09:23 PM
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Since your in Austin,Texas, I don't think it will be too hard to find a member here, that can put it on Datamaster or similar.
Sure makes it easier when you can see what the ECM is seeing/doing.
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Old Mar 19, 2008 | 11:31 PM
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you would think...
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Old Mar 23, 2008 | 05:02 PM
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Originally Posted by kenmack
Could be EGR valve in intake,(this valve controls idle)possibly has debris in it.
Expensive to replace, buy some GM intake cleaner (spray bomb)and follow instructions to the letter.
I just did this on my 4.3 vortec(same symptoms) and it has never run so good.Took about 30 minutes.
You've only got 10-12 bucks to lose and if it doesn't solve it the improved mileage is payback aftera coupla tanks.
Mine has had the same problem since I got it, I have tried everything(calibrating, cleaning, setting, resetting,and replacing the ignition and fuel system) but that....that was the suggestion given me by a(OMG) Ford Tech. I'll be all about it next weekend.
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Old Mar 26, 2008 | 12:09 AM
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Default Test drive
P.S. After letting it sit for 15-20 min. Take it out on a quiet back road,for a ten min run.
I hit passing gear about 4 times in 10 min, drove home and it idled perfect every since. (2 mths now)
GOOD LUCK POST YOUR RESULTS!!!!!!!
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