General Maintenance & Repairs Leaks | Squeaks | Clunks | Rattles | Grinds
Sponsored by:
Sponsored by: CARiD

weird problem. high idle with a/c OFF

Thread Tools
 
Search this Thread
 
Old Jun 30, 2014 | 09:46 AM
  #1  
Spink's Avatar
Thread Starter
TECH Regular
15 Year Member
iTrader: (1)
 
Joined: Nov 2006
Posts: 498
Likes: 2
From: NW Ohio
Default weird problem. high idle with a/c OFF

Had the throttle body off so I cleaned it. Now I have a high idle when the a/c is off. With a/c on it's close to normal but does take a second to drop all the way down. With a/c off it takes longer to come close to normal, gets down to 650 normal is 550, but with the a/c off as soon as I take my foot off the brake the idle jumps up to 1000 and stays there until I come to a complete stop for a few seconds. Only with the a/c off. With the a/c on it doesn't jump up, it behaves normally.

I've replaced the IAC Valve and tried several pcm and iac resets. Also driven the car close to 100 miles to try to let it re-learn. Checked for vacuum leaks and the pcv system is new and has no leaks.

Any ideas? Don't have access to a scan tool either. I'm at the point where I'm gonna make an appointment to have the dealer reflash it if I can't figure this out soon. Any and all suggestions appreciated.
Reply
Old Jul 1, 2014 | 08:17 PM
  #2  
blade2222's Avatar
TECH Apprentice
 
Joined: Jul 2007
Posts: 364
Likes: 0
Default

Pull the iac valve out and push the plunger all the way down then reinstall, reset your pcm by pulling the pcm battery fuse for 10 minutes. I had a problem like yours after cleaning my throttle body also.
Reply
Old Jul 2, 2014 | 11:03 AM
  #3  
Spink's Avatar
Thread Starter
TECH Regular
15 Year Member
iTrader: (1)
 
Joined: Nov 2006
Posts: 498
Likes: 2
From: NW Ohio
Default

I tried that and still ding the same thing. Is there some sort of sensor that sends a signal to the cpu telling it when the a/c is on or off. It's like it thinks the ac is on when it isn't so it increases the rpm's.

Even if that's the case though you'd think my rpms would then jump up when the compressor isn't cycling but it doesn't do that. With a/c on it's really close to normal.

With a//c off i'm idling at 39 mph. If I shift it out of overdrive and into drive the rpms jump up even more and it holds the speed at 39mph.
Reply




All times are GMT -5. The time now is 04:01 AM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE