PCM Diagnostics & Tuning HP Tuners | Holley | Diablo
Sponsored by:
Sponsored by:

What controls AC air/fuel?

Thread Tools
 
Search this Thread
 
Old 07-26-2004, 08:41 PM
  #1  
TECH Addict
Thread Starter
 
Another_User's Avatar
 
Join Date: Feb 2004
Posts: 2,826
Likes: 0
Received 0 Likes on 0 Posts
Default What controls AC air/fuel?

Is there something else that controls air/fuel with the AC on? Or does the change just have to do with increased load on the engine? Or is there some table that would be beneficial in the future for us to be able to edit?
Old 07-26-2004, 09:47 PM
  #2  
FormerVendor
iTrader: (1)
 
HumpinSS's Avatar
 
Join Date: Feb 2002
Location: Waldorf, MD
Posts: 3,059
Likes: 0
Received 0 Likes on 0 Posts
Default

In edits new verison they added values to add air when the ac is turned on. Me thinks we will see it in the next release of Tuners
Old 07-26-2004, 11:07 PM
  #3  
wrencher
iTrader: (2)
 
wrencher's Avatar
 
Join Date: Aug 2002
Location: Chicagoland
Posts: 4,762
Likes: 0
Received 0 Likes on 0 Posts

Default

It is in the PCM to begin with under A/C request, it will add IAC.
Old 07-27-2004, 09:50 AM
  #4  
TECH Addict
Thread Starter
 
Another_User's Avatar
 
Join Date: Feb 2004
Posts: 2,826
Likes: 0
Received 0 Likes on 0 Posts
Default

I am not so much interested in the AC as I am in the fact that I think there is less surging with my AC on. I have been trying to decide where to change to eliminate surging, and I was just curious if it really did add IAC. Interesting...
Old 07-27-2004, 02:32 PM
  #5  
TECH Addict
 
marc_w's Avatar
 
Join Date: Oct 2003
Location: Central, MA
Posts: 2,620
Likes: 0
Received 0 Likes on 0 Posts

Default

FWIW: In HPT for my '04 Silverado here, in regards to AC on / AC off variables, I only have the desired idle speed table. Nothing else. The TB is drive by wire.

I found it strange that both my AC on, and AC off idle speeds were the same. For the heck of it, I set the idle speed to be 50 rpm higher when my AC was on. All it did was confuse the truck when the compressor cycled. The engine idled pretty bad, and this is with an almost bone-stock motor. I set them back to the same RPM, and it idles great.
Old 07-27-2004, 04:41 PM
  #6  
FormerVendor
 
gameover's Avatar
 
Join Date: Jan 2003
Location: Melbourne, Australia
Posts: 525
Likes: 0
Received 0 Likes on 0 Posts
Default

we will be adding all the stuff i mentioned in my post on the IAC operation soon, as well as the ability to log these and other idle related things in the scanner that cannot be retrieved via normal PIDs.

There is no "AC on" fuel as such, just an idle airflow correction to open the IAC more to account for the extra load.

Chris...




All times are GMT -5. The time now is 08:45 PM.