Idle high when cold tryes to die when warmedup

Tiny
SCOTT CONNOR
  • MEMBER
  • 1988 CHEVROLET CELEBRITY
  • 122,234 MILES
Replaced iacv tpi o2 egr vac hoses still runs same serges at idle to started this after battery went wife left dome light on. Has not thrown code to ecm tryed every thing I can think of stumped.
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Sunday, July 29th, 2012 AT 11:14 PM

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Tiny
WRENCHTECH
  • MECHANIC
  • 20,757 POSTS
Idle control is a learned strategy and when the battery is discharged or disconnected, the PCM loses it's adaptive memory and has to learn it over again. Clean the throttle body first and then disconnect the battery to start over and drive it normally and it should relearn after a few miles.

Here is the cleaning process.
Make sure it has no vacuum leaks first.

Remove the intake snorkel, have someone hold the throttle wide open for you and scrub the back side of the throttle plate and surrounding bore with an old tooth brush and some carb cleaner. Be sure to spray some into the small holes next to the throttle plate. That should help stabilize the idle.
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Sunday, July 29th, 2012 AT 11:21 PM
Tiny
SCOTT CONNOR
  • MEMBER
  • 4 POSTS
Have driven car 1000 or so miles after cleaning TB have unhooked bat several times still runs the same could it be ESC or MAS
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Monday, July 30th, 2012 AT 12:28 AM
Tiny
WRENCHTECH
  • MECHANIC
  • 20,757 POSTS
Then you're going to need a professional scan tool and an expert to analyze it to diagnose it correctly.
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Monday, July 30th, 2012 AT 12:31 AM
Tiny
SCOTT CONNOR
  • MEMBER
  • 4 POSTS
I MENT emc IT RUNS OUT ON ROAD JUST NOT AT IDLE HAVE REPAIR MANUAL NOT HELPING
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Monday, July 30th, 2012 AT 12:55 AM
Tiny
SCOTT CONNOR
  • MEMBER
  • 4 POSTS
PUT A SCANER ON THE CAR IT TELLS ME EVERYTHING IS WITH IN SPEC EVEN JUMPED ECM PORT NO CODES IN ECM
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Monday, July 30th, 2012 AT 1:02 AM
Tiny
WRENCHTECH
  • MECHANIC
  • 20,757 POSTS
The data tells a story if you know how to read it.
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Monday, July 30th, 2012 AT 1:05 AM

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