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Idling problem

  • Thread starter Thread starter LxVert
  • Start date Start date May 4, 2005
L

LxVert

Member
Dec 26, 2003
80
0
6
May 4, 2005
#1
  • May 4, 2005
  • #1
Hey guys,

I have a slight problem, when i start my car up it will idle at about 700 rpms, after driving the car for a couple minutes then stopping at a light for say, it will idle at 1500 rpms, but if i turn the car off then right back on the idle will be right at 700 again. Im so lost on what could be causing this

1990 5.0
 
Q

Quijibow_69

New Member
Apr 17, 2004
44
0
0
Mechanicsburg, PA
May 4, 2005
#2
  • May 4, 2005
  • #2
Your idle control motor might be bad. I had the same problem, except when I started mine up it would almost stall and it would sit at 1500 RPMs when I was at a stop sign or light. I just replaced mine and it fixed my problem. I got mine from www.50resto.com. It was around 70 bucks, but you might be able to get one cheaper from EBay or Pep Boys or something.
 

RYC CUKR

Founding Member
May 19, 2002
1,437
1
38
Orlando
May 4, 2005
#3
  • May 4, 2005
  • #3
before you replace the IAC go ahead and clean it.

Unplug it and unbolt it from the TB. Most of the time it has a bunch of carbon and gunk in there. Clean it out with some TB cleaner and see if that helps. Also take a can of starting fluid and spray the gaskets and vacuum hose connections on the intake to make sure that you don't have a vacuum leak as well.

Here is a nice write up on cleaning the IAC and some other things to check when you have idle issues

http://www.muscularmustangs.com/iac.php
 

jrichker

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Mar 10, 2000
27,512
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Dublin GA
May 4, 2005
#4
  • May 4, 2005
  • #4
Most certainly clean the IAC, and if that doesn't work, replace the TPS. See the Sticky " Help me create the Surging Idle Checklist" at the top of the forum for more help.
 
L

LxVert

Member
Dec 26, 2003
80
0
6
May 4, 2005
#5
  • May 4, 2005
  • #5
Thanks guys for the info, i will clean everything really well then let you know how it comes out
 
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