PCM Diagnostics & Tuning HP Tuners | Holley | Diablo

Startup is very lean, 19.2 on W/B

Thread Tools
 
Search this Thread
 
Old May 22, 2007 | 07:32 PM
  #1  
Blown Interceptor's Avatar
Thread Starter
TECH Apprentice
iTrader: (5)
 
Joined: Apr 2004
Posts: 399
Likes: 0
From: San Diego, Ca
Default Startup is very lean, 19.2 on W/B

I adjust the idle airflow vs coolant temp a while ago, could this be why I am so lean?


Here is where I set it.
Attached Thumbnails Startup is very lean, 19.2 on W/B-mvc-110f.jpg  
Reply
Old May 22, 2007 | 08:14 PM
  #2  
Violatorno1's Avatar
12 Second Club
20 Year Member
iTrader: (3)
 
Joined: May 2004
Posts: 189
Likes: 0
From: Altoona, PA
Default

What type of WB? Is it just when you first fire it? I'm using an LC-1 hooked to EFILive. When you first fire the car the WB needs to heat up and set. While this is happening the Innovate software reads "Warming up" on the guage and the readiness light flashes. During this time my A/F reads 19-20.1 until the WB warms and the light goes solid. I'm sure this would be the same for any WB.
Reply
Old May 22, 2007 | 08:29 PM
  #3  
Blown Interceptor's Avatar
Thread Starter
TECH Apprentice
iTrader: (5)
 
Joined: Apr 2004
Posts: 399
Likes: 0
From: San Diego, Ca
Default

Originally Posted by Violatorno1
What type of WB? Is it just when you first fire it? I'm using an LC-1 hooked to EFILive. When you first fire the car the WB needs to heat up and set. While this is happening the Innovate software reads "Warming up" on the guage and the readiness light flashes. During this time my A/F reads 19-20.1 until the WB warms and the light goes solid. I'm sure this would be the same for any WB.

It's an LC-1 w/gauge. Yeah, goes down to around 14.7 when the car warms up. Sounds normal...

Thanks
Reply
Old May 22, 2007 | 09:16 PM
  #4  
SSpdDmon's Avatar
TECH Addict
iTrader: (10)
 
Joined: Jun 2004
Posts: 2,918
Likes: 0
From: Commerce Twp, MI
Default

It's probably the AIR pump (assuming you still have it attached). It injects outside air/oxygen into the exhaust on start up.
Reply
Old May 22, 2007 | 10:26 PM
  #5  
ujslost2's Avatar
Launching!
20 Year Member
Photogenic
Photoriffic
Shutterbug
iTrader: (27)
 
Joined: Jul 2004
Posts: 218
Likes: 0
From: Alabama
Default

Yes, lowering the values in the idle airflow will cause it to go leaner. The PCM thinks its getting less air in the motor, therefore less fuel. And vice versa. Try increasing the values some and see what happens.
Reply
Old May 23, 2007 | 10:10 AM
  #6  
SSpdDmon's Avatar
TECH Addict
iTrader: (10)
 
Joined: Jun 2004
Posts: 2,918
Likes: 0
From: Commerce Twp, MI
Default

Originally Posted by ujslost2
Yes, lowering the values in the idle airflow will cause it to go leaner. The PCM thinks its getting less air in the motor, therefore less fuel. And vice versa. Try increasing the values some and see what happens.
The idle airflow values have nothing to do with fueling. It's just a starting point to find the correct airflow for idle. The STIT's and LTIT's will keep it where it needs to be airflow wise assuming they're not maxed out because of inaccurate information in the base airflow table.

Fueling needs to be adjusted in the fueling tables.

Again, this issue is most likely the AIR pump skewing the WBO2 data. Depending on the year, the AIR pump will operate for up to 3~4 minutes after startup. That fresh air hitting the WBO2 will appear as a lean AFR.
Reply
Old May 23, 2007 | 12:33 PM
  #7  
brad8266's Avatar
TECH Senior Member
iTrader: (23)
 
Joined: Aug 2005
Posts: 8,797
Likes: 0
From: Watertown, NY
Default

Originally Posted by SSpdDmon
The idle airflow values have nothing to do with fueling. It's just a starting point to find the correct airflow for idle. The STIT's and LTIT's will keep it where it needs to be airflow wise assuming they're not maxed out because of inaccurate information in the base airflow table.

Fueling needs to be adjusted in the fueling tables.

Again, this issue is most likely the AIR pump skewing the WBO2 data. Depending on the year, the AIR pump will operate for up to 3~4 minutes after startup. That fresh air hitting the WBO2 will appear as a lean AFR.
Reply




All times are GMT -5. The time now is 07:15 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