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  • Fox 5.0 Mustang Tech

IAC Adjuster

  • Thread starter Thread starter ATISTANG
  • Start date Start date Mar 30, 2009

ATISTANG

Member
Apr 15, 2006
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Mar 30, 2009
#1
  • Mar 30, 2009
  • #1
anyone use one of these? do they work alright?

I wonder if they will lean the mixture out through any amount of throttle

reason i was curious is I have the worst luck raising my idle without getting idle surge


86-93 IAC ADJUSTER MUSTANG
 

ShortThrow50

Member
Oct 22, 2006
923
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Pa
Mar 30, 2009
#2
  • Mar 30, 2009
  • #2
i use one and it works great for modified cars. especially works well with idle. if you want to raise your idle, you will just install it and then loosen the screws the same amount a little at a time and it will bypass the iac.
 

ATISTANG

Member
Apr 15, 2006
104
0
16
Mar 30, 2009
#3
  • Mar 30, 2009
  • #3
ShortThrow50 said:
i use one and it works great for modified cars. especially works well with idle. if you want to raise your idle, you will just install it and then loosen the screws the same amount a little at a time and it will bypass the iac.
Click to expand...

ok, so it feeds more air all the time? or just at idle? i don't want to risk leaning out.
 

ShortThrow50

Member
Oct 22, 2006
923
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Pa
Mar 30, 2009
#4
  • Mar 30, 2009
  • #4
no not all the time. the holes are so small, its only gonna affect your idle and not the driveability or the air/fuel ration under part throttle or acceleration. you will be fine
 

jrichker

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  • Mar 31, 2009
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Fix the source of the problem and don't just band-aid it...

See the "Surging Idle Checklist for help with all your idle/stall problems. Everything you need to find and fix idle problems is in there.

The first two posts contain all the updates to the fixes. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.
 

bubba-dough

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Dec 28, 2004
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Mar 31, 2009
#6
  • Mar 31, 2009
  • #6
I am not a fan of having to put something on or using a band-aid to fix a problem, so do the link jrichker posted and eliminate most of the issues asociated with surges.

With that being said, I had to use one on my dd 347 and it fixed my problem right away. I had went through everything probably 5x and nothing fixed my problem.
 

ShortThrow50

Member
Oct 22, 2006
923
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Pa
Mar 31, 2009
#7
  • Mar 31, 2009
  • #7
he has a highly modified car guys. this plate is very helpful with fine tuning for cars like this. It does the job in which it is made to do. alot of guys such as my self found this peice as a very useful tool and not a bandaid. if the car wasnt cammed or modified, then i would say there was a problem elsewhere and the plate would be a bandaid
 

bubba-dough

Active Member
Dec 28, 2004
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#8
  • Mar 31, 2009
  • #8
Read my entire post. Thanks.
 

jrichker

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#9
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  • #9
The problem with surging idle/stall conditions is that they can be caused by a number of different things. Simple problems like defective sensors and turbulent airflow throw the MAF can be difficult to spot without a comprehensive diagnostic approach.

The idea is to eliminate the things that are working properly and thus shrink down the list of possibilities from 24 to 2 or 3. It is much easier (and cheaper) to work with the 2 or 3 item list than the 24 item list.

Make sure the engine will idle smoothly at 600-650 RPM with the IAC (or IAB) disconnected before spending money on the Ford Idle Air Adjuster gizmo.
 

ATISTANG

Member
Apr 15, 2006
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Apr 1, 2009
#10
  • Apr 1, 2009
  • #10
jrichker said:
Fix the source of the problem and don't just band-aid it...

See the "Surging Idle Checklist for help with all your idle/stall problems. Everything you need to find and fix idle problems is in there.

The first two posts contain all the updates to the fixes. At last count there were 24 possible causes and fixes for surging idle/stall problems. I continue to update it as more people post fixes or ask questions.
Click to expand...

thanks, i'll run through that

as ShortThrow said i have a sizable cam, and a blower that blows through the MAF, i think most of my problems have to do with the blow through setup. Eventually i plan to change over to a suck through MAF

when i first got it tuned it idled pretty good, then i let the battery die once and jump started it, every since it has idle surged, I'm relocating the battery back to the front anyways because once i put it in the hatch i have had all kinds of stupid problems
 

bubba-dough

Active Member
Dec 28, 2004
1,044
2
38
Indiana
Apr 1, 2009
#11
  • Apr 1, 2009
  • #11
Not saying you did, but there is a right way and a wrong way to jump a vehicle. Most people do it the wrong way. This can cause all sorts of electrical/electronic problems. Also there is a right and many many wrong ways to relocate the battery. Do a search for the battery relocation and you will find the right way. jrichker (I believe) has a very good right-up/ schematic.
 

jrichker

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Apr 1, 2009
#12
  • Apr 1, 2009
  • #12
Battery relocation tech notes

Rear mounted battery ground wiring. Follow this plan and you will have zero
ground problems.


One 1 gauge or 1/0 gauge wire from battery negative post to a clean shiny spot
on the chassis near the battery. Use a 5/16” bolt and bolt it down to make the
rear ground. Use a 1 gauge or 1/0 gauge wire from the rear ground bolt to a clean
shiny spot on the block.

One 4 gauge wire from the block where you connected the battery ground wire to
the chassis ground where the battery was mounted up front. Use a 5/16” bolt
and bolt down the 4 gauge engine to chassis ground, make sure that it the metal
around the bolt is clean & shiny. This is the alternator power ground.




The computer has a dedicated power ground wire with a cylindrical quick connect
(about 2 ½”long by 1” diameter. It comes out of the wiring harness near the
ignition coil & starter solenoid (or relay). Be sure to bolt it to the chassis ground
in the same place as you bolted the alternator power ground. This is an
absolute don’t overlook it item for EFI cars

Note: The quick disconnect may have fallen victim to damage or removal by
a previous owner. However, it is still of utmost importance that the black/green
wires have a high quality ground..

The screwdriver points to the common body ground for the alternator, battery and computer.

Picture courtesy timewarped1972



Crimp or even better, solder the lugs on the all the wire. The local auto stereo
shop will have them if the auto parts store doesn't. Use some heat shrink tubing
to cover the lugs and make things look nice.

For a battery cut off switch, see Moroso : Category Display
is the switch http://www.moroso.com/catalog/images/74102_inst.pdf is the installation instructions.
Use the super duty switch and the following tech note to wire it and you will
be good to go.

Use the Moroso plan for the alternator wiring and you risk a fire. The 10
gauge wire they recommend is even less adequate that the stock Mustang
wiring.

There is a solution, but it will require about 40' of 18 gauge green wire.

Wire the battery to the two 1/2" posts as shown in the diagram.

The alternator requires a different approach. On the small alternator plug
there is a green wire. It is the sense lead that turns the regulator on when
the ignition switch is in the run position. Cut the green wire and solder the
40' of green wire between the two pieces. Use some heat shrink to cover the
splices. See Ford Fuel Injection How To Solder Like a Pro for some excellent
help on soldering & using heat shrink tubing.

Run the green wire back to the Moroso switch and cut off the excess wire.
Try to run the green wire inside the car and protect it from getting cut or
chaffed. Crimp a 18 gauge ring terminal (red is 18 gauge color code for the crimp
on terminals) on each wire. Bolt one ring terminal to each of the 3/16" studs.
Do not add the jumper between the 1/2" stud and the 3/16" stud as shown it the
Moroso diagram.

How it works:
The green wire is the ignition on sense feed to the regulator. It supplies a turn
on signal to the regulator when the ignition switch is in the Run position. Turn the
Moroso switch to off, and the sense voltage goes away, the voltage
regulator shuts off and the alternator quits making power.

The fuse & wiring in the following diagram are for a 3G alternator. The stock alternator uses a dark green fuse link wire that connects to 2 black/orange wires. Always leave them connected to the starter solenoid even if you have a 3G alternator.



See the following website for some help from Tmoss (diagram designer)
& Stang&2Birds (website host) for help on 88-95 wiring
Mustang FAQ - Engine Information Everyone should bookmark this site.

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg
 

Cobra912

Active Member
May 1, 2005
1,777
11
39
Wish I was anywhere but here
Apr 1, 2009
#13
  • Apr 1, 2009
  • #13
mine didn't work for me........I ended up getting a tune........solved it
 

ATISTANG

Member
Apr 15, 2006
104
0
16
Apr 3, 2009
#14
  • Apr 3, 2009
  • #14
jrichker said:
Battery relocation tech notes

Rear mounted battery ground wiring. Follow this plan and you will have zero
ground problems.


One 1 gauge or 1/0 gauge wire from battery negative post to a clean shiny spot
on the chassis near the battery. Use a 5/16” bolt and bolt it down to make the
rear ground. Use a 1 gauge or 1/0 gauge wire from the rear ground bolt to a clean
shiny spot on the block.

One 4 gauge wire from the block where you connected the battery ground wire to
the chassis ground where the battery was mounted up front. Use a 5/16” bolt
and bolt down the 4 gauge engine to chassis ground, make sure that it the metal
around the bolt is clean & shiny. This is the alternator power ground.




The computer has a dedicated power ground wire with a cylindrical quick connect
(about 2 ½”long by 1” diameter. It comes out of the wiring harness near the
ignition coil & starter solenoid (or relay). Be sure to bolt it to the chassis ground
in the same place as you bolted the alternator power ground. This is an
absolute don’t overlook it item for EFI cars

Note: The quick disconnect may have fallen victim to damage or removal by
a previous owner. However, it is still of utmost importance that the black/green
wires have a high quality ground..

The screwdriver points to the common body ground for the alternator, battery and computer.

Picture courtesy timewarped1972



Crimp or even better, solder the lugs on the all the wire. The local auto stereo
shop will have them if the auto parts store doesn't. Use some heat shrink tubing
to cover the lugs and make things look nice.

For a battery cut off switch, see Moroso : Category Display
is the switch http://www.moroso.com/catalog/images/74102_inst.pdf is the installation instructions.
Use the super duty switch and the following tech note to wire it and you will
be good to go.

Use the Moroso plan for the alternator wiring and you risk a fire. The 10
gauge wire they recommend is even less adequate that the stock Mustang
wiring.

There is a solution, but it will require about 40' of 18 gauge green wire.

Wire the battery to the two 1/2" posts as shown in the diagram.

The alternator requires a different approach. On the small alternator plug
there is a green wire. It is the sense lead that turns the regulator on when
the ignition switch is in the run position. Cut the green wire and solder the
40' of green wire between the two pieces. Use some heat shrink to cover the
splices. See Ford Fuel Injection How To Solder Like a Pro for some excellent
help on soldering & using heat shrink tubing.

Run the green wire back to the Moroso switch and cut off the excess wire.
Try to run the green wire inside the car and protect it from getting cut or
chaffed. Crimp a 18 gauge ring terminal (red is 18 gauge color code for the crimp
on terminals) on each wire. Bolt one ring terminal to each of the 3/16" studs.
Do not add the jumper between the 1/2" stud and the 3/16" stud as shown it the
Moroso diagram.

How it works:
The green wire is the ignition on sense feed to the regulator. It supplies a turn
on signal to the regulator when the ignition switch is in the Run position. Turn the
Moroso switch to off, and the sense voltage goes away, the voltage
regulator shuts off and the alternator quits making power.

The fuse & wiring in the following diagram are for a 3G alternator. The stock alternator uses a dark green fuse link wire that connects to 2 black/orange wires. Always leave them connected to the starter solenoid even if you have a 3G alternator.



See the following website for some help from Tmoss (diagram designer)
& Stang&2Birds (website host) for help on 88-95 wiring
Mustang FAQ - Engine Information Everyone should bookmark this site.

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg
Click to expand...
my ground is set up almost the same minus the ground cable from the body ground at the rear to the engine. I will try to add that and go from there

now as for the regulator green wire, why is that necessary?
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
2,811
234
Dublin GA
Apr 3, 2009
#15
  • Apr 3, 2009
  • #15
ATISTANG said:
my ground is set up almost the same minus the ground cable from the body ground at the rear to the engine. I will try to add that and go from there

now as for the regulator green wire, why is that necessary?
Click to expand...

The additional green wire shuts off the alternator in the same manner as the stock wiring. It prevents the alternator from generating a huge electrical spike when the battery is disconnected. That electrical spike can damage the alternator, computer, radio and other electrical accesories you may have like a GPS or stereo.
 

ATISTANG

Member
Apr 15, 2006
104
0
16
Apr 4, 2009
#16
  • Apr 4, 2009
  • #16
jrichker said:
The additional green wire shuts off the alternator in the same manner as the stock wiring. It prevents the alternator from generating a huge electrical spike when the battery is disconnected. That electrical spike can damage the alternator, computer, radio and other electrical accesories you may have like a GPS or stereo.
Click to expand...

so thats if the car is running and you throw the switch right?
 

ATISTANG

Member
Apr 15, 2006
104
0
16
Apr 4, 2009
#17
  • Apr 4, 2009
  • #17
bubba-dough said:
Not saying you did, but there is a right way and a wrong way to jump a vehicle. Most people do it the wrong way. This can cause all sorts of electrical/electronic problems. Also there is a right and many many wrong ways to relocate the battery. Do a search for the battery relocation and you will find the right way. jrichker (I believe) has a very good right-up/ schematic.
Click to expand...

i let it charge on low amp for about an hour, then flipped the charger to the high amp (jump start) setting and cranked.
 

jrichker

StangNet's favorite TOOL
In Remembrance. Thank you for your contributions
Mar 10, 2000
27,512
2,811
234
Dublin GA
Apr 4, 2009
#18
  • Apr 4, 2009
  • #18
ATISTANG said:
so thats if the car is running and you throw the switch right?
Click to expand...

Yes. Most drag racing organizations require an externally accessible switch to turn off the engine/battery in case of a crash.

If you did crash at the track, it would be better if the rescue crew didn't do any more damage when they turned off the battery...
 

ATISTANG

Member
Apr 15, 2006
104
0
16
Apr 4, 2009
#19
  • Apr 4, 2009
  • #19
jrichker said:
Yes. Most drag racing organizations require an externally accessible switch to turn off the engine/battery in case of a crash.

If you did crash at the track, it would be better if the rescue crew didn't do any more damage when they turned off the battery...
Click to expand...

it would probably be better if my switch wasn't in the hatch also lol
 
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