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Higher Idle

  • Thread starter Thread starter dcurtis
  • Start date Start date May 13, 2007

dcurtis

10 Year Member
Jan 19, 2006
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May 13, 2007
#1
  • May 13, 2007
  • #1
Ok, I desided to clean my throttle body and my IAC the other day because when I first start my car in the morning it would die the first time or two, got them clean and put them back on and tried it again and I thought it was fixed but when I took it for a drive later that day I noticed my idle was staying around 900 to 1000 at idle, car runs a lot smoother and better now but the idle is just a bit high now that things are working right, so how do I lower my idle the right way? I was told to unhook the advance on the dizzy and unhook the IAC and check the timing and then set my idle at 600 with the throttle screw on the throttle body, then disconnect the battery and hook everything back up, wait about ten minutes and hook the battery back up, then turn the key to the run position and set or check the TPS voltage, once voltage is correct to the TPS, fire it up.
Is this right??
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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May 13, 2007
#2
  • May 13, 2007
  • #2
Had you ever adjusted the stop screw? That's the one biggie that is not manipulated by the computer. If it was set to allow the base idle to be above that of the commanded idle (with zero IAC DC), there is not a lot the puter can do to lower the idle setting back down.

A sticky IAC can indeed cause your issue. It will often generate a limit code.

Jrichker's idle surge sticky has lots of info, tips and tricks which might be helpful.

Good luck.
 

jrichker

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May 13, 2007
#3
  • May 13, 2007
  • #3
See "Surging Idle Checklist for help with all your idle problems. The first two posts contain all the updates to the fixes. I continue to update it as more people post fixes or ask questions.
 
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