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Retraining your IAC?

  • Thread starter Thread starter keepinitril
  • Start date Start date Nov 19, 2009

keepinitril

Member
Mar 24, 2009
102
1
18
Anaheim Hills
Nov 19, 2009
#1
  • Nov 19, 2009
  • #1
Im having an issue when I start my 90 GT.
Itll start and about half(the other half it just dies) the time itll surge and at it will go from 400 rpm to about a grand and I believe its just the IAC.
Ill fight that by tapping the gas

This started after I jumped my buddys car, but before it would idle at 550/600 now its dead on the line at 500.

I also noticed it feels like it has a misfire, but then if I put it into gear(forward or reverse) and hold the brake, it goes away(it an automatic)

any thoughts or insight?
does it sound like an IAC issue?
 

tannerc91gt

This last 25% is foreign territory at this point
Founding Member
Nov 29, 1999
4,392
2,967
234
Indiana
Nov 19, 2009
#2
  • Nov 19, 2009
  • #2
keepinitril said:
Im having an issue when I start my 90 GT.
Itll start and about half(the other half it just dies) the time itll surge and at it will go from 400 rpm to about a grand and I believe its just the IAC.
Ill fight that by tapping the gas

This started after I jumped my buddys car, but before it would idle at 550/600 now its dead on the line at 500.

I also noticed it feels like it has a misfire, but then if I put it into gear(forward or reverse) and hold the brake, it goes away(it an automatic)

any thoughts or insight?
does it sound like an IAC issue?
Click to expand...

IAC would cause it to idle pretty high and stay there on a cold start up. the surging could be caused by a number of things. definitly go through the surging idle check list - http://www.stangnet.com/mustang-forums/698148-help-me-create-surging-idle-checklist.html

check vac leaks, tps, etc.

good luck
 

keepinitril

Member
Mar 24, 2009
102
1
18
Anaheim Hills
Nov 19, 2009
#3
  • Nov 19, 2009
  • #3
when I swapped my heads, I redid all of the vaccuum lines, as well as the pcv valve, and the pcv grommit
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Nov 19, 2009
#4
  • Nov 19, 2009
  • #4
As noted in the Idle surge sticky, start with pulling codes. You should have generated an idle limit code at a minimum.
 

keepinitril

Member
Mar 24, 2009
102
1
18
Anaheim Hills
Nov 19, 2009
#5
  • Nov 19, 2009
  • #5
no codes have been generated
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Nov 19, 2009
#6
  • Nov 19, 2009
  • #6
You should at least get a code 11. If you are not getting it, something is wrong.
 
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