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Stoplight Surgeing??????????

  • Thread starter Thread starter BluThnder99
  • Start date Start date Dec 10, 2004
B

BluThnder99

New Member
Aug 29, 2003
201
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St. Louis
Dec 10, 2004
#1
  • Dec 10, 2004
  • #1
I have notice in the last couple of days my car surges at stoplights, does anybody have any idea what is causing this?
 
S

sgramer

Founding Member
Feb 6, 2002
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16
San Rafael, Ca
Dec 10, 2004
#2
  • Dec 10, 2004
  • #2
Ideas

How long have you had the plenum, K&N, and the cold air kit. You may need to clean your MAF, because of the K&N oil. You may need to reset the computer because, of the plenum. Do you have a bend in front of the MAF, because of the CAI, if so you may need to change that.


Scott
 
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BluThnder99

New Member
Aug 29, 2003
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St. Louis
Dec 10, 2004
#3
  • Dec 10, 2004
  • #3
sgramer said:
How long have you had the plenum, K&N, and the cold air kit. You may need to clean your MAF, because of the K&N oil. You may need to reset the computer because, of the plenum. Do you have a bend in front of the MAF, because of the CAI, if so you may need to change that.


Scott
Click to expand...


The MAF is stock and I haven't cleaned the K&N yet.
 

daver01

Founding Member
Oct 4, 2002
396
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Lexington, Ky
Dec 10, 2004
#4
  • Dec 10, 2004
  • #4
my car did something similar to this earlier in the year. it would kinda 'hunt' for idle when i was stopped at a light, but sounded more like it does when the a/c is running. (idle going up & down)

may not be exactly the problem u are having; but after i cleaned the iac with carb cleaner, the prob. went away. worth a shot; only takes a min.
 

jrc_03_gt

New Member
Jan 1, 2004
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Dec 11, 2004
#5
  • Dec 11, 2004
  • #5
do you have underdrive pulleys?
 
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BluThnder99

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Aug 29, 2003
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St. Louis
Dec 11, 2004
#6
  • Dec 11, 2004
  • #6
jrc_03_gt said:
do you have underdrive pulleys?
Click to expand...


No underdrive pulleys but I'll try cleaning my IAC though thanks fo rthe tip.
 
S

SRMobile

Trend Micro poster child
Jun 1, 2004
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Dec 11, 2004
#7
  • Dec 11, 2004
  • #7
Try disconnecting the battery for 15 mins and let the computer relearn everything.
 

big o car 4.6

Founding Member
Jan 3, 2002
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dallas
Dec 11, 2004
#8
  • Dec 11, 2004
  • #8
What is the IAC
 

big o car 4.6

Founding Member
Jan 3, 2002
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dallas
Dec 11, 2004
#9
  • Dec 11, 2004
  • #9
jrc_03_gt said:
do you have underdrive pulleys?
Click to expand...

and what would that have to do with it
 
S

SRMobile

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Jun 1, 2004
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Dec 11, 2004
#10
  • Dec 11, 2004
  • #10
Idle Air Control... Apparently its a comon problem on the stangs and usualy needs cleaning replacing after a good amount of millage.

Symptoms include stalling and having to give a little gas in order to keep the engine going while idling.
 

JonJon

Founding Member
Aug 16, 2002
4,801
1
68
back in Marylands
Dec 11, 2004
#11
  • Dec 11, 2004
  • #11
I don't know if it would be the IAC... but if yours starts to idle fine, well I'll go check mine out.
 

StangIt #1

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Oct 25, 2001
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Washing the Car
Dec 11, 2004
#12
  • Dec 11, 2004
  • #12
SRMobile said:
Idle Air Control... Apparently its a comon problem on the stangs and usualy needs cleaning replacing after a good amount of millage.

Symptoms include stalling and having to give a little gas in order to keep the engine going while idling.
Click to expand...

...and, if your '97 GT still has the factory-issue IAC, it's probably time for it to go bad. The one on my '98 went last year, so be prepared to drop around $70-$80 (can't remember for sure) for a new one from Ford. The IAC on our GT's ('96-'98) is a little aluminum piece with at least 1 vacuum hose stuck into it and some type of black plastic "valve" looking piece on the side of it. You can find it bolted just in front of your upper plenum. BTW, cleaning the IAC is only a temporary fix, because the valve spring inside of the unit is probably worn out.
 
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SRMobile

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Jun 1, 2004
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Dec 11, 2004
#13
  • Dec 11, 2004
  • #13
big o car 4.6 said:
and what would that have to do with it
Click to expand...

Under drive pulleys do exacly as the name states. It underdrives the accesories on the engine in order to free up some power. I did this with my last car and when at a stop light, my lights would dim, AC would slow down and the idle would be quite low.
 

JonJon

Founding Member
Aug 16, 2002
4,801
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68
back in Marylands
Dec 11, 2004
#14
  • Dec 11, 2004
  • #14
SRMobile said:
Under drive pulleys do exacly as the name states. It underdrives the accesories on the engine in order to free up some power. I did this with my last car and when at a stop light, my lights would dim, AC would slow down and the idle would be quite low.
Click to expand...
But did you idle surge a lot?
Mine will go from 1000 to 500 to 700, and repeat. I assume the thread starter has the same problem.
 
S

SRMobile

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Jun 1, 2004
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Dec 11, 2004
#15
  • Dec 11, 2004
  • #15
My regular idle in my other car before I put in the UDP was just under 1000 and would work its way down slowly to 900ish. After I did the change it would idle around 900 and go as low as 700. It wouldnt idle as smooth as it did before but it never stalled.
 
S

SRMobile

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Jun 1, 2004
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Dec 11, 2004
#16
  • Dec 11, 2004
  • #16
Come to think of it, is it possible that its just the compressor cycling ?
 
F

ForPointSex

Founding Member
Mar 19, 2002
395
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Mercer, NJ
Dec 11, 2004
#17
  • Dec 11, 2004
  • #17
Clear or replace your IAC. Here's a picture if you don't know where it's at. http://www.geocities.com/joop1987/iac.jpg
 
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