Page 1 of 2 12 LastLast
Results 1 to 10 of 18

Thread: AFR, Closed Loop and Lean Cruise (Shhhhh...)

  1. #1
    Senior Member Wolfie's Avatar
    Join Date
    Dec 2007
    Posts
    182

    Default AFR, Closed Loop and Lean Cruise (Shhhhh...)

    This may be a dumb question, but I couldn't find an answer...
    Now, I am running open loop, with afr set at 15 and also lean cruise...
    Can I go back to running closed loop with the proper afr, but would
    the lean cruise still function properly? or would the o2 sensors keep
    trying to change the afr???
    Wolfie
    LS1B 2007 Express 6.0 /w 470,000+ miles (parked as of 01April2011)

  2. #2
    Lifetime Member swingtan's Avatar
    Join Date
    Jul 2007
    Posts
    1,589

    Default

    Basically, run COS-3 and "semi-OL".

    Where ever you command stoich, ( 14.63:1 ) the O2's will turn on and adjust the fueling. Otherwise they are turned off in the tune and you run OL.

    Simon

  3. #3
    Senior Member Wolfie's Avatar
    Join Date
    Dec 2007
    Posts
    182

    Default

    Can't run a cos.
    What I mean, is, will lean cruise still kick in, or will the o2s keep trying to over ride it?
    Wolfie
    LS1B 2007 Express 6.0 /w 470,000+ miles (parked as of 01April2011)

  4. #4
    Joe (Moderator) joecar's Avatar
    Join Date
    Apr 2003
    Posts
    28,403

    Default

    If you have true lean cruise then it should kick in when all the conditions for it are met.

  5. #5
    Senior Member Wolfie's Avatar
    Join Date
    Dec 2007
    Posts
    182

    Default

    Thanks Joe.
    That is what I was looking for.
    I had been running ol for 300,000 miles,
    but thought I would try going back to cl.
    Wolfie
    LS1B 2007 Express 6.0 /w 470,000+ miles (parked as of 01April2011)

  6. #6
    Senior Member
    Join Date
    Feb 2008
    Posts
    169

    Default

    You should always keep in mind that LC was built for E0%.
    Running E10% on a E0% program works out to about 15.3 to 1 AFR.
    If you run E10 on a LC program you will be leaner than you think.
    The Factory LC programs that I have looked at have a lot more than just leaning the car out.
    Hmmmmmm maybe I could post some of that.
    Cal Editor aka A.J.
    Lead Calibrator at PCM Calibrators
    ASE Master Certified since 1988 -- ASE L1, F1 & A9
    GM Technician since 1999 -- GM World Class Technician since 2009
    CNG Installer -- CSA Inspector
    A handful of people out there who do have an intimate knowledge of GM Calibrations

  7. #7
    Lifetime Member Chevy366's Avatar
    Join Date
    Oct 2006
    Posts
    1,603

    Default

    Just did LC patch couple days ago , and like Joe says once the parameters are satisfied it kicks in .
    From what I have seen LC just looks at kPas and RPM pretty simple , kind of reminded me of the COS3 B3647 and how you can target certain kPa at given RPMs and achieve the same thing .
    1-0.1152=.8848 , 14.7/.8848= 16.61 AFR this is very close in LC table .
    Last edited by Chevy366; January 22nd, 2010 at 11:15 AM.
    2005 1500 HD , Custom OS3 SD tune .
    2006 Trailblazer
    Dinosaurs and Plants gave their lives so that we may drive , long live fossil fuel .

  8. #8
    Senior Member
    Join Date
    Feb 2008
    Posts
    169

    Default

    do you know what a dbf is?
    Cal Editor aka A.J.
    Lead Calibrator at PCM Calibrators
    ASE Master Certified since 1988 -- ASE L1, F1 & A9
    GM Technician since 1999 -- GM World Class Technician since 2009
    CNG Installer -- CSA Inspector
    A handful of people out there who do have an intimate knowledge of GM Calibrations

  9. #9
    Senior Member Wolfie's Avatar
    Join Date
    Dec 2007
    Posts
    182

    Default

    quoted- snip...
    If you run E10 on a LC program you will be leaner than you think.

    I was sure that my wb with its own controller would keep me informed of afr.

    dbf?

    dBase? Danmarks Badminton Forbund? Digital Beam-Forming? Dynamic Beam Forming?
    Deep Blues Festival? Densified Biomass Fuel? Danish Beekeepers Federation?
    Drude-Born-Federov? Distributed Bellman-Ford? yes? no? Do I need to know?
    Wolfie
    LS1B 2007 Express 6.0 /w 470,000+ miles (parked as of 01April2011)

  10. #10
    Senior Member
    Join Date
    Feb 2008
    Posts
    169

    Default

    Quote Originally Posted by Wolfie View Post
    quoted- snip...
    If you run E10 on a LC program you will be leaner than you think.

    I was sure that my wb with its own controller would keep me informed of afr.

    dbf?

    dBase? Danmarks Badminton Forbund? Digital Beam-Forming? Dynamic Beam Forming?
    Deep Blues Festival? Densified Biomass Fuel? Danish Beekeepers Federation?
    Drude-Born-Federov? Distributed Bellman-Ford? yes? no? Do I need to know?
    Sorry about that
    I meant the dbf for Chevy366
    Cal Editor aka A.J.
    Lead Calibrator at PCM Calibrators
    ASE Master Certified since 1988 -- ASE L1, F1 & A9
    GM Technician since 1999 -- GM World Class Technician since 2009
    CNG Installer -- CSA Inspector
    A handful of people out there who do have an intimate knowledge of GM Calibrations

Page 1 of 2 12 LastLast

Similar Threads

  1. closed loop problem on cruise
    By gto reynolds in forum Gen IV V8 Specific
    Replies: 0
    Last Post: November 2nd, 2008, 10:30 AM
  2. How to REALLY shut of closed loop/ force open loop
    By Tomato in forum Gen III V8 Specific
    Replies: 6
    Last Post: June 17th, 2008, 02:37 AM
  3. Closed Loop Lean Cruise Idea (O2 Switch Points)
    By BlackGMC in forum Gen III V8 Specific
    Replies: 0
    Last Post: October 25th, 2007, 07:18 AM
  4. dfco and lean cruise in OS3 semi open loop mode
    By ringram in forum General (Petrol, Gas, Ethanol)
    Replies: 3
    Last Post: November 16th, 2005, 08:02 AM
  5. Open Loop SD VS Closed Loop SD Advantages???
    By BowlingSS in forum General (Petrol, Gas, Ethanol)
    Replies: 1
    Last Post: August 4th, 2005, 11:25 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •