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Thread: Too lean to AutoVE test/tune !!??!?! Why?

  1. #1
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    Default Too lean to AutoVE test/tune !!??!?! Why?

    I am trying to dail my car in with the AutoVE tutorial but my A/Fs are too lean to do any kind of decent pulls through the gears. The car idles around 16:1, part throttle is between 15-18:1 and WOT is never richer than 14:1 and often as lean as 16:1 @ WOT

    What am I doing wrong? How can I make the car richer (safe!) so I can actually log and get good counts in all the AFR cells?

    I have 37# injectors in the car and tried adjusting the IFR up and down 10% from the base tune but the A/Fs don't seen to change! I also did an open air calibration on my LC-1 before any of this tuning.

  2. #2
    foff667
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    Quote Originally Posted by Learning
    I am trying to dail my car in with the AutoVE tutorial but my A/Fs are too lean to do any kind of decent pulls through the gears. The car idles around 16:1, part throttle is between 15-18:1 and WOT is never richer than 14:1 and often as lean as 16:1 @ WOT

    What am I doing wrong? How can I make the car richer (safe!) so I can actually log and get good counts in all the AFR cells?

    I have 37# injectors in the car and tried adjusting the IFR up and down 10% from the base tune but the A/Fs don't seen to change! I also did an open air calibration on my LC-1 before any of this tuning.
    going from stock injectors to 37# is more then a 10% move...i highly recommend using one of the injector calculators floating around on the net to get your ifr the way it should be.

  3. #3
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    Quote Originally Posted by foff667
    going from stock injectors to 37# is more then a 10% move...i highly recommend using one of the injector calculators floating around on the net to get your ifr the way it should be.
    Let me try this again My IFR has been set more or less correctly from day one but the car is running too lean to drive hard for accurate AutoVE tuning.

    I tried altering the IFR up and down 10% from the original 37# setting (actual numbers in the IFR cells are 41.X-42.X) and no matter what I change the car is still too lean. Does this sound strange or am I missing something?

    Update

    I just plugged all my injector numbers into this handy tool that joecar pointed me to and it says my numbers should be in the 43.X-46.X range.

    I will adjust this in my tune but would it be enough to throw my AFs way out? Actually, by making the IFR number larger won't I make the car run leaner?

  4. #4
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    You could try adding 10-15% to your whole VE table and then see where it's at.

    After setting the IFR with the spreadsheet you shouldn't have to mess with it again, it should really be a "set it and leave it" table from what I understand.
    1992 Turbo LSX Notchback Mustang 275 radial car - under construction
    2008 Sierra 2500HD Duramax

  5. #5
    Lifetime Member SSpdDmon's Avatar
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    If you have a wideband (which you should if your tuning your car), you can force the car into open-loop operation (up the closed loop enable temps to 256*F). Then, go into the Fueling In Open Loop (Normal) table and command a safe AFR (12.0~12.5) for everything above ECT of 140*F. Get the lower portion of the VE table squared away with AutoVE. Then, based on what you see in the lower portion, make an educated guess on where the upper portion needs to be. Then, go tune the upper portion with AutoVE. Make sense? Don't forget to disable DFCO, COT, etc.

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    Lifetime Member TAQuickness's Avatar
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    Quote Originally Posted by SSpdDmon
    If you have a wideband (which you should if your tuning your car), you can force the car into open-loop operation (up the closed loop enable temps to 256*F). Then, go into the Fueling In Open Loop (Normal) table and command a safe AFR (12.0~12.5) for everything above ECT of 140*F. Get the lower portion of the VE table squared away with AutoVE. Then, based on what you see in the lower portion, make an educated guess on where the upper portion needs to be. Then, go tune the upper portion with AutoVE. Make sense? Don't forget to disable DFCO, COT, etc.

    don't forget to disable the MAF while you are tuning


  7. #7
    Lifetime Member TAQuickness's Avatar
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    How you doing with this?


  8. #8
    Lifetime Member SSpdDmon's Avatar
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    Quote Originally Posted by TAQuickness
    don't forget to disable the MAF while you are tuning
    Yeah, that too.

    (It was supposed to be included in that "etc," which was meant to cover the MAF, spark high>low, changing commanded AFR, and so on.)

    Just to be thorough, these are the tables that need to be changed:

    1) Disable MAF & MAF MILS (high fail freq = 1Hz, fail limit = 1)
    2) Disable DFCO (change temp enabler to 256*F)
    3) Disable COT (if not done already)
    4) Disable LTFTs
    5) Copy High Spark to Low Spark (watch for KR after extensive mods - ie heads/cam)
    6) Disable Closed-loop (change temp enablers to 256*F)
    7) Change commanded AFR in Open Loop fueling and PE (I like to use one value for all ranges in operating temps - ie 12.0AFR.)

    I believe that's everything. Remember - if using the NBO2's to tune, you only want to do 1-5 and use the average STFT %'s to adjust your tune (caution - see note bellow about longtubes). 6 & 7 are for WB tuning only. Once you get the VE dialed in with the above settings, re-enable the MAF and tune each MAF table frequency with the same % error (logged AFR divided by commanded AFR) method used on the VE until everything comes back in line. Then, return the remaining tables to stock or your desired values.

    ** NOTE ** If fuel trims still aren't close, there's potentially a problem with the stock O2's (noticeable with some longtube headers - ie slow switching or colder O2 operating temps) or the WBO2 you used to tune with (check for voltage variances - sensor commanded voltage vs. voltage read by scanner).

    Did I get it all this time???
    Last edited by SSpdDmon; April 19th, 2006 at 03:16 AM.

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