Cold start--up and down idle

Deths91Gt

Founding Member

Sep 30, 1998

1,394

3

39

KS

Dec 12, 2003

#1

• Dec 12, 2003

• #1

I know this is a newbie question--i just recently got back into the Mustang scene. But everyone of my cars ive had over the last 10 years have idled like crap when cold--i have to sit there and rev the motor up until it will stay at the same RPM. Is it the IAC?? Doesnt seem to be a vacuum leak--car runs and idles fine when its warmed up. Major Mods consist of E-cam and Longtubes and H-pipe--its a Speed Density but even my MAS cars have done this. Thanks.

 

P

PsYLenT-G

New Member

Dec 12, 2003

7

0

0

Columbus, OH

Dec 13, 2003

#2

• Dec 13, 2003

• #2

I have an all stock 91 GT and have a similar problem. see my thread for more information: 'Idle issues... Can anyone help? '

 

S

staticc

Founding Member

Sep 28, 2002

234

0

0

Jupiter, FL

Dec 13, 2003

#3

• Dec 13, 2003

• #3

im right in the same boat. longtube and b cam.

 

X

xplo89gt

Founding Member

Jul 14, 1999

945

0

16

Boston, MA

Dec 13, 2003

#4

• Dec 13, 2003

• #4

same boat, didnt start happening til i installed heads, intake, tfs stage 1 cam.

i've checked about everything except the ECT sensor. I will probably replace that ($30) to see.

 

HO5POINTO1990

New Member

Aug 12, 2003

125

0

0

San Jose

Dec 13, 2003

#5

• Dec 13, 2003

• #5

I have the same problem but not when cold but rather THE SECOND START... i start it the first time and there are no problems... but then when i start it again that day or anytime that day it doesn't idle correctly. It kinda bounces up and down till it fixes itself... or i rev it up once or twice to get it to stay above 750 rpms. Oh well.

 

DirtyD916

Active Member

May 25, 2003

804

1

38

Norcal 916

Dec 13, 2003

#6

• Dec 13, 2003

• #6

get some carb cleaner and clean out the throttle body. Then clean out all the hoses and connections involved or connected to the throttle body. Also adjust the idle on the throttle body.
Just remember that most cars dont strat good in the cold. just let it warm up.