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

My GT won't run

  • Thread starter Thread starter 99RedGTman
  • Start date Start date Aug 31, 2004
9

99RedGTman

New Member
Dec 28, 2003
16
0
0
Ohio
Aug 31, 2004
#1
  • Aug 31, 2004
  • #1
Ok, I have a 1999 GT. It will start up fine, doesn't take any longer than normal to start it, but once I start it up, it dies, unless I hold the throttle at any position, even If I were to hold it at about 900 RPMs, it will run. Now I checked all the Vaccum lines I could find, but none of them are blown off. People are telling me it may be my MAF or the Air idle control motor, or an O2 sensor. I am just wondering if any of those would throw a CEL? I am just wondering because if they don't, then something is really wrong, because I am not getting a CEL. Any help would be appreciated.
 

StangLou

Active Member
Jul 9, 2003
1,264
0
36
Holly Springs, NC
Aug 31, 2004
#2
  • Aug 31, 2004
  • #2
Its sounding a lot like your IAC is shot. They seem to go left and right on these cars Mine is an '03 and Im on my 3rd replacement IAC. Thankfully its lasted almost a year!!! Some people say you can clean them, but its really just going to give you the same problem in a few weeks if you just clean it. These things control the air within certain "specs" Whenever it gets out of "spec" you get this problem you are talking about. Just buy you a new one from autozone or something. I know 5.0 resto has them as well.
 
9

98GreenGT

Founding Member
Aug 22, 2000
207
0
0
Miami, Fl
Aug 31, 2004
#3
  • Aug 31, 2004
  • #3
Its the IAC alot of people have this problem, the o2 will cause a check engine light and so will the MAF.
 
9

99RedGTman

New Member
Dec 28, 2003
16
0
0
Ohio
Aug 31, 2004
#4
  • Aug 31, 2004
  • #4
Cool, I'm gonna run out and buy one right now. Hopefully that is the problem.

I'll probably change the PCV valve too
 
U

UNVMATT

New Member
Jan 15, 2004
294
0
0
COLUMBUS
Aug 31, 2004
#5
  • Aug 31, 2004
  • #5
My IAC went bad in my 2000 GT went bad and had this problem. No idiot light came on. Thankfully it is a manual and its easy to push in the clutch and keep on the throttle while sitting at traffic lights.

My 2001 Escape had the same problem..But the check engine light did come on in it..

You can buy the IAC (Idle Air Control) Solenoid for your car for around 40.00 at NAPA. Its very, very simple to install. Just a couple of screws and about 5 minutes time.
 
9

99RedGTman

New Member
Dec 28, 2003
16
0
0
Ohio
Aug 31, 2004
#6
  • Aug 31, 2004
  • #6
UNVMATT said:
My IAC went bad in my 2000 GT went bad and had this problem. No idiot light came on. Thankfully it is a manual and its easy to push in the clutch and keep on the throttle while sitting at traffic lights.

My 2001 Escape had the same problem..But the check engine light did come on in it..

You can buy the IAC (Idle Air Control) Solenoid for your car for around 40.00 at NAPA. Its very, very simple to install. Just a couple of screws and about 5 minutes time.
Click to expand...

Are you in Columbus Ohio?
 

DTMach1

New Member
Jun 14, 2004
240
0
0
Virginia Beach, VA
Aug 31, 2004
#7
  • Aug 31, 2004
  • #7
IAC or a fuel filter
 
O

Origommi

New Member
Aug 14, 2004
180
0
0
Aug 31, 2004
#8
  • Aug 31, 2004
  • #8
Quick fix

I had the same problem yesterday. Before going out and buying a new IAC I pulled the air filter out, the hose and sensor and sprayed the entire thing down with carb cleaner. I then sprayed the carb (while running). After smoking like there was no tomorrow, I shut it off and started it back up again. Problem fixed, except for the check engine light which came on. I assume this came on because I sprayed the sensors (not a good idea). After driving it for a about 1/2 hour the light went off. Problem solved and it is running great.
 

KaPPaBaLL

New Member
Nov 28, 2003
1,326
0
0
BAYAREA
Aug 31, 2004
#9
  • Aug 31, 2004
  • #9
Mustangs gallop... they don't run hope your mustangs gallops soon!
 

Brisk281GT

New Member
Aug 5, 2003
340
0
0
Naperville, IL
Aug 31, 2004
#10
  • Aug 31, 2004
  • #10
Most likely the IAC as other people have said. My car was in the begining stages of this a few months ago. I had to really give it gas in order for it to carch idle sometimes. I cleaned the IAC with some carb cleaner and it seems to be ok now. They are fairly cheap though, only like $45 at Autozone.
 
9

99RedGTman

New Member
Dec 28, 2003
16
0
0
Ohio
Aug 31, 2004
#11
  • Aug 31, 2004
  • #11
I installed a new IAC, and the car runs sooooo well now. It used to run kinda rough, but the new IAC really helped out. Now not to sound dumb, but wtf does the PCV valve go? I got a new one just because.
 
R

Roger_4.6_96

Founding Member
Jul 16, 2002
1,209
0
0
Reno,NV
Aug 31, 2004
#12
  • Aug 31, 2004
  • #12
I never touched my IAC
 
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