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Where is it best to set your idle?

  • Thread starter Thread starter kpack5982
  • Start date Start date Apr 10, 2007

kpack5982

Yeah, it was pretty stiff, but eventually a buddy
Jul 13, 2005
325
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Granger, IA
Apr 10, 2007
#1
  • Apr 10, 2007
  • #1
I have my idle with Iac disconnect at about 600 and the car will run up to about 900 with the iac connected, which makes my car run fine with my mods. problem is when it is cold it will only idle at like 600 and almost wants to die. When warm it idles fine at 900. I have underdrive pullies and i know my idle needs to be up to like 900, but the question is, when you reset the idle do you set it where you want it to idle before connecting the iac? It should only go up like 100 rpm right when you connect it?
 

85ragtop

BTW, I like dudes.
10 Year Member
Nov 29, 1999
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Apr 10, 2007
#2
  • Apr 10, 2007
  • #2
You may get more help in tech.
Moved to tech.
 

jrichker

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Mar 10, 2000
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Apr 10, 2007
#3
  • Apr 10, 2007
  • #3
See "Help me create the Surging Idle Checklist" at http://forums.stangnet.com/showthread.php?t=534062
for help with your idle problems. The answer to your question is in there. The first post contains all the updates to the fixes. I continue to update it as more people post fixes or ask questions.
 

kpack5982

Yeah, it was pretty stiff, but eventually a buddy
Jul 13, 2005
325
1
19
Granger, IA
Apr 10, 2007
#4
  • Apr 10, 2007
  • #4
yeah, i was just wondering what everyone sets their idle at. I know how to set it and all, I was just curious if you should set it where you WANT the idle before reconnecting the IAC or should I expect the Idle to go up and set it slightly lower based on it wanting to go up?
 

onefstsnake

New Member
Nov 25, 2005
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Northern VA
Apr 10, 2007
#5
  • Apr 10, 2007
  • #5
I think ford says it should be somewhere around 600-750

But mine wants to stall at anything under 800. Seems like alot of modded 5.0's dont want to idle at factory specs.
 

jrichker

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Apr 10, 2007
#6
  • Apr 10, 2007
  • #6
The base mechanical idle setting procedure is in the Surging Idle tech note, along with an explanation of how the IAC works to control the idle speed.

The low voltage output as a result of underdrive pulleys can aggravate idle problems.
 
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