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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

Supercharged and high idle

  • Thread starter Thread starter ef200098
  • Start date Start date Jun 16, 2005
E

ef200098

New Member
Dec 20, 2004
123
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0
Jun 16, 2005
#1
  • Jun 16, 2005
  • #1
is my iac bad? ive checked eight times for vaccum leaks but cant find anything. or is the supercharger just blowing air through the TB? with the car out of gear it idles at about 2000-1500. should i try changing the iac? or can i just clean it out, how do i clean it out?

thanks
mike
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jun 16, 2005
#2
  • Jun 16, 2005
  • #2
ef200098 said:
is my iac bad? ive checked eight times for vaccum leaks but cant find anything. or is the supercharger just blowing air through the TB? with the car out of gear it idles at about 2000-1500. should i try changing the iac? or can i just clean it out, how do i clean it out?

thanks
mike
Click to expand...

You might try a pcm reset.

Later
Grady
 
E

ef200098

New Member
Dec 20, 2004
123
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0
Jun 16, 2005
#3
  • Jun 16, 2005
  • #3
tried and still high idle. i could possibly have a leak between the upper and lower, but i seriously doubt that is it. what else can i do to at least determine if its my iac or not?
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jun 16, 2005
#4
  • Jun 16, 2005
  • #4
ef200098 said:
tried and still high idle. i could possibly have a leak between the upper and lower, but i seriously doubt that is it. what else can i do to at least determine if its my iac or not?
Click to expand...

Pull the plug on it and see if the rpms drop.

Later
Grady
 

mo_dingo

20+ Year Stangneter
Aug 26, 2003
3,031
2
58
Tucson, AZ
Jun 16, 2005
#5
  • Jun 16, 2005
  • #5
Attempts to clean the IAC valve usually result in a permenantly broken IAC valve. I have seen it personally, and multiple times here. IDK why, they just break when you expose them to carb cleaner.

See if you can close your TB stop screw more and your IAC valve screw more and see what happens.

If not, your IAC valve may be bad. Get a new one at pep boys (borg/warner part is only match, AZ doesn't stock the right one) and see what happens.
Scott
 
E

ef200098

New Member
Dec 20, 2004
123
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Jun 17, 2005
#6
  • Jun 17, 2005
  • #6
what about advanced? no pep boys around here.
 
E

ef200098

New Member
Dec 20, 2004
123
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0
Jun 17, 2005
#7
  • Jun 17, 2005
  • #7
tb stop is down as well as the iac screw and when i let the screw out it idles at about 2k and when its all the way down i idle at about 1.5k rpm. im going to go get a new iac valve and see if that corrects the problem, if it doesn't im driving the car off a cliff.


is there anyway i can find out if i have a vaccum leak or not?
 

dstanggt50

Founding Member
Sep 13, 2000
1,316
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0
Woodinville, WA
Jun 17, 2005
#8
  • Jun 17, 2005
  • #8
ef200098 said:
tb stop is down as well as the iac screw and when i let the screw out it idles at about 2k and when its all the way down i idle at about 1.5k rpm. im going to go get a new iac valve and see if that corrects the problem, if it doesn't im driving the car off a cliff.


is there anyway i can find out if i have a vaccum leak or not?
Click to expand...

You can spray some carb cleaner in certain areas and see if the rpms climb, or chk with a vacuum guage, most auto stores sell em.
 
E

ef200098

New Member
Dec 20, 2004
123
0
0
Jun 17, 2005
#9
  • Jun 17, 2005
  • #9
i have a vac/boost gauge, it reads at about 22" at idle. what should my vac be at idle?
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Jun 17, 2005
#10
  • Jun 17, 2005
  • #10
Did the idle drop when you pulled the iac plug?

Later
Grady
 
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