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Thread: Commanded AFR not equal to WBo2 AFR at idle.

  1. #1
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    Default Commanded AFR not equal to WBo2 AFR at idle.

    G'day all, I think this is my very first post on this forum, having been a long time lurker and reader.

    I own a 2001 HSV Senator 300 M6, which has an LS1 engine - ETP215 heads, Comp 215/223 @111lsa camshaft and all the rest of the good gear.

    I recently purchased EFIlive - after doing the spannerwork on my engine mods and have enjoyed an immense amount of assistance from forum regulars here - JezzaB, macca_779 and Swingtan.

    I'm running MAFless - OLSD - as the car came stock with this configuration and I'm using EFIlive COS3. I updated to the latest drivers / Firmware, etc yesterday.

    JezzaB provided me with a good base tune and the other two have assisted with tweaks to dial it right in for me.

    I've reached a point where it is running extremely well - great manners and the driveability is excellent. It is making around 395rwhp at the top and around 411lb/ft torque.

    Anyway, I've been playing around with my idle settings lately - going through the tutorials written by Weatherman Shawn and others (thanks lads), but have come to a point where I am a little perplexed.

    At idle my commanded AFRs are not corresponding to the WBo2 readings. I know the gearis dialled in correctly, because the AFR readings match when off-idle and throughout the rev-range - well, within a couple of percent anyway.

    I've attached a copy of my latest iteration of a tune and the accompanying idle log.

    What do you think? Any assistance would be greatly appreciated.

    cheers
    Attached Files Attached Files

  2. #2
    Lifetime Member swingtan's Avatar
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    I can't remember if you said that you'd adjusted the VE table, but it looks likes it's just a bit high in the idle cells. The VE is very "smooth" for an LS1 so I'd do a couple of auto VE passes over it to clean it up. If you really don't want to touch the VE table in other areas because you like the way it runs, you can manually adjust the VE just in the idle cells. Just take about 7% out of the idles cells.

    Simon.

  3. #3
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    Thanks mate - I did go a tad strong with the smoothing after I did an AutoVE (I like smooth!), so I may do as you say and see how it goes from there.

    cheers

  4. #4

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    map your BEN and make adjustments from your idle log. What thermo stat are u running? . If it's a 160f then change to 71c (currently at 60C / 140f).

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    Just running the standard thermostat - as far as I am aware.

    I've done another autoVE, so I'll do a couple of logs and see where we end up - the new idle log is fairly close now.

  6. #6
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    Just a bit of an update - I've completed a few SDautoVE logging sessions and have managed to cover the 800-6800rpm range between 15-55kpa fairly well. I also did an idle specific one, which for my car is 800rpm / ~45kpa and then did a RAFIG to clean it all up. All is going nicely at present and the AFRs vs Commanded are very close - still some discrepancy throughout the rev range, but closing in fast.

    Thanks for your help lads.

  7. #7
    Joe (Moderator) joecar's Avatar
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    Post new files

  8. #8
    Lifetime Member mr.prick's Avatar
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    What is the AFR value for EQ 1.00?
    The stoich AFR value for your WBO2 most likely does not match the value of {B3601} exactly.
    I have seen {GM.AFR} out of sync with {B3601} and {GM.EQIVRATIO}.

    Use {EXT.WO2EQR1} and/or {EXT.WO2LAM1} with {GM.EQIVRATIO} for Gen III PCM & serial WBO2.
    You will need a new BEN factor pid(s) for this.
    ({GM.EQIVRATIO}/{EXT.WO2EQR1})
    ({GM.EQIVRATIO}*{EXT.WO2LAM1})
    512k RoadRunner Firmware 12.14R
    FlashScan V2 Bootblock V2.07.04 Firmware V2.07.22 EFILive V7.5.7 (Build 191) V8.2.1 (Build 181)
    LC-1 WBO2

    _________________________________________________

  9. #9
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    Joecar - I'll post some once I've done more logging.

    Mr Prick - I'm not 100% certain as to what you're telling me, but I'll try to digest your advice and change the PID to the calculation you are suggesting, then report back.

    Thanks

  10. #10
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    Mr Prick, I've just taken a look at your calculator and also the literature that comes with the Techedge and note that the Techedge calls AFR Stoichmetric 14.7 for the fuel I am using. Should I simply be altering my B3601 to read 13.7 or is there something I am missing?

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