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Computer learning idle question

  • Thread starter Thread starter spederman
  • Start date Start date Mar 11, 2006
S

spederman

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Apr 13, 2005
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Mar 11, 2006
#1
  • Mar 11, 2006
  • #1
I installed some bolt ons and a new tune with my XCAL2 about a month ago. I set the TPS voltage with my volt meter to 0.98V like your supposed to. It took only a day for the computer to learn how to idle normal. I thought all was good.

Well, today was the first day since last fall that i actually needed the AC on. I clicked it on and the car got all confused with the idle. It idles fine at 700-800 rpm at a stop, but as soon as i hear the click for the AC condensor kick on, the idles pop up to 1200. Once it clicks off, then it comes back down. Also, the idle hangs at 1500 RPM pretty badly with the AC on until i come to a FULL stop and then after a couple seconds at a full stop it goes down.

Does the computer have to learn the A/C idle seperately? Is this normal and will it go away as soon as it learns the idle for the A/C in a few days? I guess i just assumed that as long as it learns to idle properly, that it will do it with our without the A/C perfectly.
 
K

Kilgore Trout

Fried or Broiled ?
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Mar 30, 2005
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Mar 11, 2006
#2
  • Mar 11, 2006
  • #2
The procedure for relearning in the owners manually specifically includes turning on a/c. Check it out
 
S

spederman

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Apr 13, 2005
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Mar 11, 2006
#3
  • Mar 11, 2006
  • #3
Kilgore Trout said:
The procedure for relearning in the owners manually specifically includes turning on a/c. Check it out
Click to expand...


I saw that, and followed it the first time i ever started it after the mods. I guess i assumed that was good enough, and figured since it learned the normal idle already, some how magically it would know the A/C idle. I guess i didnt think it was two seperate idle functions and it would have to learn the A/C idle once i start using it.
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
4,749
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Mar 11, 2006
#4
  • Mar 11, 2006
  • #4
Any time you reset PCM you have to do the re-learn procedure.
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
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the people's republic of massachusetts
Mar 11, 2006
#5
  • Mar 11, 2006
  • #5
keep us posted on this. if it don't clear up we need to figure out why you have a IAC overspeed issue. and if it is a overspeed issue it should set a code.
 
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