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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Idle problem

  • Thread starter Thread starter kenshin5.0
  • Start date Start date Nov 23, 2010

kenshin5.0

New Member
Apr 4, 2010
3
0
1
Nov 23, 2010
#1
  • Nov 23, 2010
  • #1
Hey, I have a 1990 5.0 that will not idle when you first start it up if you run it down the road a while it will start to idle. But then if you shut if off for more than an hour it has the same problem. I bought this car about two years ago and the guy said all he ever did was headers and mallory ing. system. Any help would be great.
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Nov 28, 2010
#2
  • Nov 28, 2010
  • #2
Id start by cleaning your IAC valve (attached to the front side of the TB), also clean the throttle blade area in the throttle body.
 

4rdnut

Member
Dec 14, 2010
188
1
16
Dec 20, 2010
#3
  • Dec 20, 2010
  • #3
When you run it down the road and it finally idles, is the idle real low? If it is then just raise your idle.
 

Mustang5L5

That is…until I whipped out my Bissell
Mod Dude
Feb 18, 2001
43,367
18,112
224
Massachusetts
Dec 20, 2010
#4
  • Dec 20, 2010
  • #4
Moved to 5.0 tech for more visibility.


Start by cleaning the IAC. Next, perform the base idle reset procedure.

If that doesn't help, drive for a day or so and then run the check engine codes.
 
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