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Engine Hunting / stalling

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Old Jun 30, 2009 | 03:50 PM
  #16  
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I understand your thinking - it's just that I'm sure I've read before that AFM is ignored at WOT (think Adrian said so). I wondered if this was also true when the idle micro-switch was active.
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Old Jun 30, 2009 | 03:53 PM
  #17  
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The AFM is the primary load sensor so its used at idle, WOT and part-throttle.
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Old Jun 30, 2009 | 04:16 PM
  #18  
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OK - thanks.

I know I didn't imagine it - and bizarrely, I apparently even questioned it in 2003 :

https://rennlist.com/forums/showthre...eferrerid=3583

Anyway - slightly OT since it doesn't really apply to idle problems. So I will say that the only time I've had idle problems (apart from when mechanics have over-filled my oil and fouled the ISV) was when I first bought the car and had worn distributor caps / rotor arms.

Last edited by DaveK; Jun 30, 2009 at 04:47 PM.
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Old Jun 30, 2009 | 04:42 PM
  #19  
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If Jason says it...you better believe it
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Old Jun 30, 2009 | 06:00 PM
  #20  
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As others have said check the ISV. It's a quick job and if its never been done before chances are it will need it. I had this hunting idle problem for a while and cleaning the ISV didn't cure the issue, although the ISV certainly needed cleaning. I looked into many of the suggestions above, but in the end it was my distributers. They had a fair amount of carbon tracking on them. I cleaned them up as best as I could and it did help, however I still encountered the issue with reduced level of hunting. Changed them out and have had no issues for 6 plus months. Car has run noticeably better at low RPM's ever since.
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Old Jul 3, 2009 | 12:28 PM
  #21  
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david@st ives
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From: Hayle cornwall
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Eureka, I cant thank you guys enough.

Fingers crossed, everything is now working fine, I cleaned out the ISV with wd40 and a good old shake, i also hooked it up to 12 v to activate the mechanism a few times during cleaning.

I also cleaned the ISV muffler, dont know if that was wise, but i couldnt resist while it was off.

I didnt do any prodding, just copious amounts of wd40.

Just need to confirm the emissions at the garage

Now onto my next problem
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Old Jul 3, 2009 | 10:44 PM
  #22  
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Now you are ready to drop the motor and do a rebuild Good fun accomplishing something that's easy too!
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Old Jul 6, 2009 | 01:42 AM
  #23  
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From: Hayle cornwall
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I dont know if its just me, but it now feels faster and a lot more responsive.
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