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For those with IAC modifications

  • Thread starter Thread starter FalconGuy016
  • Start date Start date Jul 5, 2005
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FalconGuy016

New Member
Oct 26, 2004
437
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Northern VA
Jul 5, 2005
#1
  • Jul 5, 2005
  • #1
Hey

For anyone with either the 1/2" cap in the IAC tube or if they made the plate, does anybody else have the problem of as the car warms up it seems that the effect of the restrictors diminish? I hoped that as the temperature increased the seal around the cap became less and less airtight, but thats just a blind hope that im pretty sure I proved wrong with a lot of electrical tape. When I turn on my car, it sounds great, revs drop very quickly and it sounds really nice, driving it does the same between shifts. However as time goes on, it seems to lose this effect, but I dont think ALL the way, but a lot. Does anyone experience this or at least know whats going on?
 
S

SilverGTV8

New Member
Nov 30, 2003
295
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West Brookfield, MA
Jul 6, 2005
#2
  • Jul 6, 2005
  • #2
I never noticed that :dunno:
 

tl75keith

New Member
Jul 20, 2004
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Owings Mills, MD
Jul 6, 2005
#3
  • Jul 6, 2005
  • #3
I'm using a plate and mine doesn't do that.
 

Give Me TP

Member
Jun 17, 2004
936
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Republic of Texas
Jul 6, 2005
#4
  • Jul 6, 2005
  • #4
There is no difference in idle drop speed on mine when cold and after being warmed up. I am using a plate.
 
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FalconGuy016

New Member
Oct 26, 2004
437
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Northern VA
Jul 6, 2005
#5
  • Jul 6, 2005
  • #5
Damn!! Then what is wrong with mine... I've done both the plate and the cap, and the cap seems to work better but it still does this!
 

triggz

Founding Member
May 15, 2002
1,218
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Gadsden, AL
Jul 6, 2005
#6
  • Jul 6, 2005
  • #6
Try resetting the computer (unplug battery, hold brakes, reconnect).

Its possible for the car to learn to overcome the suffocated IAC.


Make sure you installed the cap in the right place as well, in the black rubber tube with the black box on it on the side where the hose is connected to the intake plenum.
 
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FalconGuy016

New Member
Oct 26, 2004
437
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Northern VA
Jul 6, 2005
#7
  • Jul 6, 2005
  • #7
Sigh I dont think its the computer, or at least something a reset could fix, because it works fine for a little while then changes slowly to normal. But I'm gonna try it thanks

I installed the cap past the black filter box in the longer hose that connects to the IAC. Is there a difference if I installed it in the short hose of the 90 degree bend?

Sigh!
 
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fatkidracing4.6

New Member
May 30, 2005
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Canton,Oh
Jul 6, 2005
#8
  • Jul 6, 2005
  • #8
What benefit will you get from blocking off the IAC? Call me a newbie, but i have never heard of this!
Andrew
 

mustang70

Founding Member
Nov 15, 2001
2,445
2
48
San Diego
Jul 6, 2005
#9
  • Jul 6, 2005
  • #9
fatkidracing4.6 said:
What benefit will you get from blocking off the IAC? Call me a newbie, but i have never heard of this!
Andrew
Click to expand...

It stops the hanging idle that the 4.6's have. The rpms will drop faster.

I have the plate in mine and there is no difference between cold and warmed up.
 

Twisted

Founding Member
May 14, 2002
387
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Hansen,CT
Jul 6, 2005
#10
  • Jul 6, 2005
  • #10
link to information or pictures on the plate please?
 

Give Me TP

Member
Jun 17, 2004
936
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Republic of Texas
Jul 7, 2005
#11
  • Jul 7, 2005
  • #11
http://forums.stangnet.com/showthread.php?t=470711
 

d98gt

Founding Member
Mar 14, 2002
4,505
59
204
SE Texas
Jul 7, 2005
#12
  • Jul 7, 2005
  • #12
I noticed I also have this hanging idle.. Does he have a website for these or is he still just doing it from his PMs?

I'd like one.
 

Give Me TP

Member
Jun 17, 2004
936
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Republic of Texas
Jul 7, 2005
#13
  • Jul 7, 2005
  • #13
http://search.ebay.com/_W0QQfrppZ50QQfsooZ1QQfsopZ1QQrdZ0QQsassZ34Q5fford

Does the 98 have the same type of IAC as the 99-04 models? If not there is also a way to do this mod with a copper pipe plug.
 

d98gt

Founding Member
Mar 14, 2002
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Jul 7, 2005
#14
  • Jul 7, 2005
  • #14
As far as the same type.. I have no clue
 
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w.neurauter

New Member
Apr 25, 2005
98
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0
Jul 7, 2005
#15
  • Jul 7, 2005
  • #15
For the past few months I have had the copper pulg in my 03 gt, but I made a restrictor plate at work the other day and will install today. The copper plug works well, but the revs would drop too fast with the a/c on. Does anyone know of a difference with the plate restrictor versus the sopper plug? Thanks
 

Give Me TP

Member
Jun 17, 2004
936
0
16
Republic of Texas
Jul 7, 2005
#16
  • Jul 7, 2005
  • #16
Shouldn't be any difference in performance between a plate and a copper pipe plug.
 

Give Me TP

Member
Jun 17, 2004
936
0
16
Republic of Texas
Jul 7, 2005
#17
  • Jul 7, 2005
  • #17
d98gt said:
As far as the same type.. I have no clue
Click to expand...

Probably different, knowing Ford. Does your IAC valve look like the one in the pic in the StangNet or eBay link. If not use a copper plug.
 

d98gt

Founding Member
Mar 14, 2002
4,505
59
204
SE Texas
Jul 7, 2005
#18
  • Jul 7, 2005
  • #18
Could you give me some info on this copper plug thing also?

I REALLY REALLY want to fix the hanging idle, and i'd really like to use the spacer that you 99-04 guys are using.. though it doesn't say it'll work on a 96-98

Thanks for any quick help.
 

mustang70

Founding Member
Nov 15, 2001
2,445
2
48
San Diego
Jul 7, 2005
#19
  • Jul 7, 2005
  • #19
d98gt said:
Could you give me some info on this copper plug thing also?

I REALLY REALLY want to fix the hanging idle, and i'd really like to use the spacer that you 99-04 guys are using.. though it doesn't say it'll work on a 96-98

Thanks for any quick help.
Click to expand...

PM magnum347 about the plate. I bought one from him for my 98 and it works great.
 

d98gt

Founding Member
Mar 14, 2002
4,505
59
204
SE Texas
Jul 8, 2005
#20
  • Jul 8, 2005
  • #20
Could I get some info on the copper plug?

I'll pm magnum about the plate

This might sound like a stupid question, though I noticed someone talking about the rpms while shifting gears, though I have an auto so it isn't going to decel real quick if I let off the gas... correct?


 
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