PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

Can't tune idle

Thread Tools
 
Search this Thread
 
Old Aug 2, 2007 | 10:44 PM
  #1  
Arc00TA's Avatar
Thread Starter
TECH Fanatic
iTrader: (17)
 
Joined: Apr 2007
Posts: 1,729
Likes: 1
From: The 'Nard
Default Can't tune idle

I've had this problem since a few weeks ago when I changed my plugs and O2's and put a stall in. The car idles fine but it revs up about 50 rpm and back down continuously, surging kind of. We checked it in hptuners and it was running about 16-18* of timing at idle where it should be 22-24*, so we fixed that, and it was also running somewhat rich. We made it relearn idle twice and it still does it. It also does it on deceleration with the brakes on (this makes it go into neutral and drop to idle) but much worse, by about 200-300 rpm. We tried every setting we could think of and it still does it. Anyone have an idea of where to look?
Reply
Old Aug 2, 2007 | 10:49 PM
  #2  
SSpdDmon's Avatar
TECH Addict
iTrader: (10)
 
Joined: Jun 2004
Posts: 2,918
Likes: 0
From: Commerce Twp, MI
Default

Yeah...timing should be 22~24* for idle in P/N and 30~32* for In Gear.

Look for the tables that control the IAC and spark idle overspeed/underspeed error. I know where they are in EFI Live, but not HPT.

http://forum.efilive.com/showthread.php?t=4661
Reply
Old Aug 2, 2007 | 11:51 PM
  #3  
Arc00TA's Avatar
Thread Starter
TECH Fanatic
iTrader: (17)
 
Joined: Apr 2007
Posts: 1,729
Likes: 1
From: The 'Nard
Default

Well we looked at that and it matches the stock spreadsheets that we compared it with. Pretty much everything that was off has been substituted with stock tune and it still does it. ONLY in closed loop mode so it has to be somewhere in the tune. My rear O2s seem to have disappeared, I have no cats but they don't throw any codes, not even hidden ones. Could they be affecting this? The fuel trims at idle are around -10 so pretty rich.
Reply
Old Aug 3, 2007 | 09:42 AM
  #4  
SSpdDmon's Avatar
TECH Addict
iTrader: (10)
 
Joined: Jun 2004
Posts: 2,918
Likes: 0
From: Commerce Twp, MI
Default

Proportional fueling is what I think it's called in HPT. Try reducing that to reduce your closed loop AFR swings.
Reply
Old Aug 3, 2007 | 08:11 PM
  #5  
Arc00TA's Avatar
Thread Starter
TECH Fanatic
iTrader: (17)
 
Joined: Apr 2007
Posts: 1,729
Likes: 1
From: The 'Nard
Default

Got it, will look at that tomorrow. Thanks.
Reply




All times are GMT -5. The time now is 09:47 PM.

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