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

Cars rpm's always pulse's up and Down when coming to stop.. HELP!

  • Thread starter Thread starter Highroller
  • Start date Start date Feb 4, 2004
H

Highroller

Founding Member
Oct 18, 2002
320
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Vegas
Feb 4, 2004
#1
  • Feb 4, 2004
  • #1
This is has been happening for a while, but it has since gotten worse.. As I start to come to a stop.., instead of my rpms slowly going down right at 2000 rpm they drop to 1500 and start pulsing.. like its going to die.. up.. down.. up down.. then it settles at 600 rpm's.. its very annoying.. the actualy Idle never goes below 600..

I have changed out my IAC.. what do you guys think.. do you think it could be my MAF? I have the Stock MAF on the car..
 

jeff1414

New Member
Jun 19, 2003
447
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0
Sacramento
Feb 4, 2004
#2
  • Feb 4, 2004
  • #2
mine does the same thing sometimes so hopefully some one can help us out!!!
 
H

Highroller

Founding Member
Oct 18, 2002
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Feb 4, 2004
#3
  • Feb 4, 2004
  • #3
jeff1414 said:
mine does the same thing sometimes so hopefully some one can help us out!!!
Click to expand...

It really started acting up once I switched my MAF back to stock.. Maybe I didn't position the MAF perfectly, I heard they can be tempermental (sp)
 

jeff1414

New Member
Jun 19, 2003
447
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Sacramento
Feb 4, 2004
#4
  • Feb 4, 2004
  • #4
I have never touched mine so i don't know what is wrong. maybe i need a tune up or something..?????
 

cobra killer

Founding Member
Mar 28, 2001
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dallas ga
Feb 4, 2004
#5
  • Feb 4, 2004
  • #5
99-00 is horrible about that.I've almost got it figured out tho.

The 03 model is probalby a TPS or just a dirty IAC..

The 99-00 has a glitch in the template causing it.Im trying a few things and should have an answer/fix shortly..

Tim
 

jeff1414

New Member
Jun 19, 2003
447
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0
Sacramento
Feb 4, 2004
#6
  • Feb 4, 2004
  • #6
let me know when you figure that out because i would really like to fix this problem but like i said it only happens sometimes. Thanks.......
Jeff
 
H

Highroller

Founding Member
Oct 18, 2002
320
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Vegas
Feb 4, 2004
#7
  • Feb 4, 2004
  • #7
cobra killer said:
99-00 is horrible about that.I've almost got it figured out tho.

The 03 model is probalby a TPS or just a dirty IAC..

The 99-00 has a glitch in the template causing it.Im trying a few things and should have an answer/fix shortly..

Tim
Click to expand...

Could definately be the TPS and IAC, since I took both off during my Plenum, Throttlebody install

please let us know Tim, I wonder if its hurting my ET's?

I will clean my IAC again, and check on my TPS
 

lasrred99gt

New Member
Dec 29, 2002
167
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0
Oceanside, CA
Feb 4, 2004
#8
  • Feb 4, 2004
  • #8
cobra killer said:
99-00 is horrible about that.I've almost got it figured out tho.

The 03 model is probalby a TPS or just a dirty IAC..

The 99-00 has a glitch in the template causing it.Im trying a few things and should have an answer/fix shortly..

Tim
Click to expand...

mine does it too, especially when cold.
 
B

Bgt2000

New Member
Aug 5, 2003
6
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Quakertown, PA
Feb 4, 2004
#9
  • Feb 4, 2004
  • #9
mine does that also but it only does it when i have the defroster on so i'm not sure
 

Brisk281GT

New Member
Aug 5, 2003
340
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0
Naperville, IL
Feb 4, 2004
#10
  • Feb 4, 2004
  • #10
My eagle talon used to do that pretty violently, I was told by all that it is probably a sensor of some kind.
 
H

Highroller

Founding Member
Oct 18, 2002
320
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Feb 5, 2004
#11
  • Feb 5, 2004
  • #11
Bgt2000 said:
mine does that also but it only does it when i have the defroster on so i'm not sure
Click to expand...

I agree regarding the defroster and or A/C.. I wish I could bring this to FORD and have them check it out, but they will point and laugh when they see my mods.. and there goes my warranty. even though I don't think they have anything to do with this problem
 

00VERT GT

New Member
Jun 30, 2003
376
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0
SW Florida
Feb 5, 2004
#12
  • Feb 5, 2004
  • #12
i've had the same problem since i've bought my car. Ford does NOT have a fix for it they say it's normal. (even though the ford rep said he had never seen it bofore) -jerks- I have replaced my IAC twice in hope that maybe that might work........nothing. haven't tried replacing the MAF yet. It looks like they aren't very cheap.
 
2

281Ponies

New Member
Nov 14, 2003
190
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0
Feb 5, 2004
#13
  • Feb 5, 2004
  • #13
My 00GT does this as well. It’s as if the computer is attempting to adapt - find the correct idle rpm, consistently searching for it but never quite finds it. At best it temporarily seems to settle in at a correct idle only to start searching for it again.

-Cale
 
H

Highroller

Founding Member
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Vegas
Feb 5, 2004
#14
  • Feb 5, 2004
  • #14
281Ponies said:
My 00GT does this as well. It’s as if the computer is attempting to adapt - find the correct idle rpm, consistently searching for it but never quite finds it. At best it temporarily seems to settle in at a correct idle only to start searching for it again.

-Cale
Click to expand...

very good description.. I don't really worry about it dying.. because it settles down around 1k.. but i hate when it happens.. it can't be good
 
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