Results 1 to 5 of 5

Thread: afr on dash vs. afr on log

  1. #1
    Potential Tuner
    Join Date
    Dec 2007

    afr on dash vs. afr on log

    have been dialing in the car and once I got it on point to my understandings.. afr on my datalogging is spot on and afr on my dash reading pig rich.. am I doing something wrong??? doing flex fuel tuning btw. is this usual or am I doing something really wrong? WOT fueling on the log is right at .82-.85(not commanded afr) but showing afr of 10.2-11.3 on the dash. car is a 2018 GT.

    i'll try uploading a log file tomorrow since I didn't bring the laptop home with me. I just keep thinking about it and want to get the thorn off my back. any help is appreciated. thanks in advance.

  2. #2
    Depending on the ethanol content, that dash reading may be correct. Just go by the lambda reading in the scanner.

  3. #3
    Advanced Tuner
    Join Date
    Mar 2010
    New Orleans, LA
    the stupid idiots at ford used AFR for the dash gauge instead of lambda so you have to factor in the stoich value its currently at in order to know if its rich or lean. Without knowing that the gauge in itself is pretty useless.

    if your logged lambda is where you set it and your fuel trims are good then just ignore the gauge

  4. #4
    Potential Tuner
    Join Date
    Mar 2019
    Got a question.. even if it was a gasoline scaled read out from lambda on the dash shouldn't it still be accurate?

    .82 lambda read out on gasoline scale is still roughly 12 : 1. The o2 sensor doesn't care about the fuel type... just the o2 left.
    Why would e85 change the gauge readout?
    This seems to be a common thing with e85 but it doesn't seem like it should be.

    Command .82 lambda in 93 octane and then in e85... if the o2 scale is set to gasoline shouldn't the final reading the same?

  5. #5
    Again, Go by lambda in the scanner.
    2009.5 PBM G8 GXP M6 W/Roof-Self tune, OBX LTs, Kooks axleback, LSA blower, cam,
    Monster LT1-SC clutch, flex fuel, 12 psi 10.41@138.7 1,800 D.A
    2007 TBSS-Self tune, bolt ons 12.9@107.3, 1,900 D.A
    1991 GMC Syclone- Self tune/catback 12.8@104, 4,200ft D.A