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2200 rpm idle!!!

  • Thread starter Thread starter 5.0Torx
  • Start date Start date Sep 10, 2008

5.0Torx

Active Member
Dec 30, 2007
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Sep 10, 2008
#1
  • Sep 10, 2008
  • #1
hey all, i fired up the beast today and it went to 1100 rpm or so, like usual, and then all of the sudden went to 2200 rpm. still held about 20 inches of vacuum. i shut her down, restarted, and its been acting normal ever since.

why do i get the feeling this is one of those problems thats either going to get worse as time goes on, or cost me $45,000 to fix? whats going on?
 

90limited

Founding Member
Apr 13, 2002
276
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Port Charlotte FL
Sep 10, 2008
#2
  • Sep 10, 2008
  • #2
My guess would be the IAC (Idle air control I think) valve. Sometimes they stick and sometimes they go bad. Part is under $100 and takes 10 minutes to put on.
 

NIKwoaC

中國製造
15 Year Member
Oct 31, 2006
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Sep 10, 2008
#3
  • Sep 10, 2008
  • #3
An annoying/strange whistle at idle sometimes indicates a failing IAC valve. You can take apart the IAC, hose it out with carb & TB cleaner, and put it back together. That sometimes will fix it, and keep it from sticking. If not, you'll have to buy a new one.
 

5.0Torx

Active Member
Dec 30, 2007
252
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29
Sep 10, 2008
#4
  • Sep 10, 2008
  • #4
actually, come to think of it, i do hear a whistle at startup but i figured it was my lack of an air silencer.

also, would a bad IAC stop it from fast idling (1300) in the winter? ive noticed that itll go to 1100-1300 now thats its moving into fall, but when its butt ass cold outside, it is hard to start and idles at 800.
 
B

bentley429

Banned
Nov 25, 2004
528
3
0
Connecticut
Sep 10, 2008
#5
  • Sep 10, 2008
  • #5
When its running at the 2200 idle, unplug the IAC if the rpms drop to normal thats the problem. May be able to just clean it, Ive never had luck with that though.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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Sep 10, 2008
#6
  • Sep 10, 2008
  • #6
bentley429 said:
When its running at the 2200 idle, unplug the IAC if the rpms drop to normal thats the problem. May be able to just clean it, Ive never had luck with that though.
Click to expand...

Sound advice here, on both counts.

I don't recommend cleaning an IAC unless someone is already prepared to buy a new one. The attempt to clean them can do more harm than good.
 

jrichker

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Mar 10, 2000
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Dublin GA
Sep 10, 2008
#7
  • Sep 10, 2008
  • #7
See the "Surging Idle Checklist for help with all your idle/stall problems. 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.
 
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