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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

HELP! Won't idle suddenly

  • Thread starter Thread starter 98GT_RagTop
  • Start date Start date Aug 18, 2004
9

98GT_RagTop

New Member
Apr 19, 2002
37
0
0
Aug 18, 2004
#1
  • Aug 18, 2004
  • #1
I have a 98 GT that has taken to not idle after starting. It goes to about 500RPM and drops to almost stall, back up, back down, then eventually quits. Also, the fan cycles on and of as the idle fluctuates. After driving for a while, it gets better, but throttle response is slow and acceleration feels 'flat'. This started out of nowhere a few days ago.

I reset the computer... no change.

I pulled off the Hypertech chip and reset... no change.

Any suggestions would be greatly appreciated.

Thanks
Bob
 
G

Ghostang

New Member
Dec 20, 2002
56
0
0
Conway, SC
Aug 18, 2004
#2
  • Aug 18, 2004
  • #2
From what I understand it could be IAC. It's the same thing mine does and I know a lot of other people are having/have had the same problem, so take a look at it and either clean it or replace it if it's dirty.
 

Red mustang Gt 46

Founding Member
Jan 12, 2001
601
0
16
Good ol' Maryland
Aug 18, 2004
#3
  • Aug 18, 2004
  • #3
There should be a sticky for the IAC...it's the IAC...$49.99 at Auto Zone...
 

Pertums

Member
Oct 31, 2003
174
0
16
NY
Aug 18, 2004
#4
  • Aug 18, 2004
  • #4
i just had the same problems last week. iac from autozone and 5 minutes of your time and it's swapped out and working like a champ again.

i went for like a month with the crappy starting revving up the motor to 'unstick' it until one day it just wouldnt hold idle anymore so i hopped in my truck to get the part.

it's 2 bolts, 1 hose, 1 wire connecter; right in front of the plenum.
 
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