What's up with my idle?

georgio440

Member

Nov 22, 2007

195

0

17

Walnut Creek, CA

Dec 2, 2007

#1

• Dec 2, 2007

• #1

It'll hover around 600RPM for a bit, then jump to around 900RPM for a little while, and then it'll go back down to 600RPM. Is this normal?

 

blkhorse

Founding Member

Oct 30, 1999

345

1

18

Dec 2, 2007

#2

• Dec 2, 2007

• #2

a/c compressor turning on? a/c also comes on when you have your heat selected to defrost

 

georgio440

Member

Nov 22, 2007

195

0

17

Walnut Creek, CA

Dec 2, 2007

#3

• Dec 2, 2007

• #3

Nope, nothing on.

 

Spro

New Member

Nov 3, 2007

73

0

0

IL

Dec 3, 2007

#4

• Dec 3, 2007

• #4

Your fan may be turning on without you even realizing it. That will make the idle come down a little bit. If not the fan, clean the IAC and see what happens.

 

281CI96Coupe

Member

Oct 30, 2006

233

0

16

Dec 3, 2007

#5

• Dec 3, 2007

• #5

It's normal lol. When stangs get old, they get the "surging idle". Everyone on this board love saying the IAC, and I believe it is.

 

joshheat25

Member

Nov 8, 2004

871

0

16

Delaware

Dec 3, 2007

#6

• Dec 3, 2007

• #6

I have that surging idle and it's done that for ahh 2 years. Only when the engine is at running temp and when it's in park. I tried everything I gave up on finding out what it is..

 

eliteJAE

Member

May 29, 2007

0

1

16

Stanford University

Dec 3, 2007

#7

• Dec 3, 2007

• #7

Spro said:

Your fan may be turning on without you even realizing it. That will make the idle come down a little bit. If not the fan, clean the IAC and see what happens.

Click to expand...

+1 it surges when the fan comes on when in idle, which is normal, and itll also surge a bit when you pump the brakes at idle, also normal.