IAC Valve or Motor??

5

5literPwr

Founding Member

Jul 17, 2002

122

3

18

Jul 3, 2009

#1

• Jul 3, 2009

• #1

When its time to replace the IAC, I see that theres the IAC "valve" and the IAC "motor". What needs to be purchased to resolve the idle and surging issues? I am running low on funds as I have already spent enough money to fix this idle issue on my 1993 GT to have bought a GT500 already. I have been just cleaning the IAC, and slapping it back on and moving to replacing something else. Please help before I take a sledgehammer to this car. I have reviewed the surge checklist and the only thing to do is get a NEW IAC instead of cleaning it. I just need to know if the motor or valve is what I need to get. Thanks in advance.

 

LiquidGT

Member

Oct 8, 2007

368

0

16

Near STL hell

Jul 3, 2009

#2

• Jul 3, 2009

• #2

IAC "Valve"/"motor"... the name is interchangeable; you get both parts when you buy one.

 

G

GTOreturns

Well-Known Member

Oct 1, 2003

51

17

59

West Coast Best Coast

Jul 3, 2009

#3

• Jul 3, 2009

• #3

I bet a 100 bux, that the IAC is not the problem. How many miles on the motor? What kind of MAF?

 

5

5literPwr

Founding Member

Jul 17, 2002

122

3

18

Jul 3, 2009

#4

• Jul 3, 2009

• #4

GTOreturns, the car has 133,000 miles on it. Its the stock MAF. I would certainly not want to spend any more money and not fix the issue, so you think its not the IAC? Thanks in advance.

 

G

GTOreturns

Well-Known Member

Oct 1, 2003

51

17

59

West Coast Best Coast

Jul 3, 2009

#5

• Jul 3, 2009

• #5

5literPwr said:

GTOreturns, the car has 133,000 miles on it. Its the stock MAF. I would certainly not want to spend any more money and not fix the issue, so you think its not the IAC? Thanks in advance.

Click to expand...

If the IAC is clean, and the gasket is good, theres a good chance thats not the problem.Go over ALL the vacuum lines and connections before sending it to a shop.

 

LiquidGT

Member

Oct 8, 2007

368

0

16

Near STL hell

Jul 3, 2009

#6

• Jul 3, 2009

• #6

Cleaning them doesnt even fix them sometimes.

I would unplug the IAC and turn the throttle body screw so that the car will idle without the IAC. I troubleshot a bad IAC like that once, the car idled fine without it plugged in; if you put a load on the engine (A/C or whatnot) without an IAC then the engine might die. If it still surges without the IAC plugged in then its something else.

 

HISSIN50

"How long does it take to get help in here?

15 Year Member

Nov 29, 1999

31,179

33

129

Jul 4, 2009

#7

• Jul 4, 2009

• #7

I've done it the way LiquidGT does as well.

 

jrichker

StangNet's favorite TOOL

In Remembrance. Thank you for your contributions

Mar 10, 2000

27,512

2,813

234

Dublin GA

Jul 4, 2009

#8

• Jul 4, 2009

• #8

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.

 

5

5literPwr

Founding Member

Jul 17, 2002

122

3

18

Jul 4, 2009

#9

• Jul 4, 2009

• #9

I unplugged the IAC and it barely wanted to idle at all and stalled out. It defintely idled worse without it. Does this completely rule out a faulty IAC? LiquidGT, it does stall out everytime I put the a/c on, so perhaps it may still be the IAC?? Also, is the T/B idle adjustment screw a Torqs head? I couldnt get a good look at it with how its positioned and the confined space. If so, what size? Thanks alot, I really appreciate it.

 

HISSIN50

"How long does it take to get help in here?

15 Year Member

Nov 29, 1999

31,179

33

129

Jul 4, 2009

#10

• Jul 4, 2009

• #10

5literPwr said:

I unplugged the IAC and it barely wanted to idle at all and stalled out. It defintely idled worse without it. Does this completely rule out a faulty IAC? LiquidGT, it does stall out everytime I put the a/c on, so perhaps it may still be the IAC?? Also, is the T/B idle adjustment screw a Torqs head? I couldnt get a good look at it with how its positioned and the confined space. If so, what size? Thanks alot, I really appreciate it.

Click to expand...

That's normal. You cannot infer anything due to the desire to stall. This test is used to see if the IAC (and/or components which command the IAC) are causing surging. Most people have their idle set low enough that the car doesn't want to idle without the IAC plugged in.

 

5

5literPwr

Founding Member

Jul 17, 2002

122

3

18

Jul 4, 2009

#11

• Jul 4, 2009

• #11

Well just like the billion other parts I've replaced, the new IAC I just replaced didnt solve the issue.

I just scanned the motor for codes and the results was a 96 code which according to my book is "Fuel pump secondary circuit fail / high speed fuel pump relay open." Does anyone know if this is a cheap easy fix, or do I need to replace the fuel pump? For some reason in KOER mode, the display stayed 000 on my scanner when I had someone keep the gas on so that it would not stall out. Does anyone know more specificaly what code 96 involves?? Thanks ALOT in advance.