Page 4 of 4 FirstFirst 1234
Results 61 to 75 of 75

Thread: 2.0 tfsi

  1. #61
    I tried everything, re-polled multiple times and not there.
    I am trying to figure out another problem in the gen 3 GM section right now. The Audi runs, on the other hand I just fired my chevelle for the first time and am having issues that I can?t figure out yet.
    Here?s a vid of the start up.
    https://youtu.be/K8DIimhBJK8

  2. #62
    They are working up a new update.

  3. #63
    Just got back from the holiday and hooked up to the car with the new update, and still a no go!

  4. #64

    Finally got my boost PID

    They gave me boots pressure and boost pressure request. I took a small log last night.
    Attached Files Attached Files
    My Avatar is my Wife and Proud of it!!
    1970 Chevelle SS 8.1 Vortec T56 9" 3.00
    2006 3500HD 8.1 vortec Allison 6sp 4.10 4X4
    2013 Audi A5 Cab 2.0tfsi Quatro
    www.mcmnapa.com

  5. #65
    Why would I have 14.9 psi at idle? Also my accelerator doesn?t match my TPS.

  6. #66
    Tuner
    Join Date
    Jul 2019
    Location
    Wilmington, MA, USA
    Posts
    71
    It sounds like you're looking at an absolute pressure. Absolute pressure has its zero point at a total vacuum, so without vacuum or boost it'll read atmospheric pressure which usually is around 14.5 PSI at sea level, less as you go up in altitude. The fact it's reading higher than 14.5 means you may be looking at the sensor that's in between the turbo and the throttle body, and the pressure is > 14.5 because the turbo is generating a small about of boost. Or it could just be the atmospheric pressure was high that day.

    Re the TPS: as you probably know our cars have electronic throttle bodies. The throttle plate position will not always match the pedal position... in fact it rarely will. Plus the TB and the accelerator pedal both have two potentiometers on them. So you've got two measurements of pedal position which don't necessarily go from 0-100 because the electrical range is greater than the mechanical range and other aspects of the design, and the same is true of the throttle body. Then with the TB you've got "desired", "commanded", and "actual". I'm pretty sure VAG also throws in a few other random numbers with the word "throttle" in the description just to piss off people like us.

    For me the answer to the TPS question is just log every value you can find that appears throttle-related, then if you're lucky you'll find one that goes 0-100 corresponding to pedal position.

  7. #67
    Good info. Makes sense. Where I live we are below sea level so that is probably why it is 14.9. Should I set up a table and filter out the 14.9? The TB makes sense, but with GM you can tune the TB and Petal rate. I can?t find a table for this. Now that I can log boost I?ve been setting up the scanner differently and the load tables are starting to make sense to me. I just think it is weird that at 60% petal I have 85% throttle.

  8. #68
    Tuner
    Join Date
    Sep 2019
    Location
    ON, Canada
    Posts
    84
    I would basically forget everything you knew about tuning in relation to GM vs VAG they are just such different systems that the knowledge hardly every crosses over.

    The reason you are getting WOT at 60% pedal is because it?s requesting enough cylinder filling to dictate a WOT request after you reach WOT filling request any filling requests higher than that are achieved with the electronic boost control solenoid (N75) with boost....

    The pedal requests an optimum torque value then the torque value translates to a load (cylinder filling)

    And yes the boost reading is from the charge piping so it will never go lower than atmospheric pressure because it never sees vacuum

  9. #69
    Is it normal for a stock 2.0 to have 30 psi of boost?
    Or does this have a tune already.

  10. #70
    Tuner
    Join Date
    Jul 2019
    Location
    Wilmington, MA, USA
    Posts
    71
    In terms of absolute pressure, yes. About 15 PSI of atmosphere plus about 15 PSI of boost = the 30 PSI you're seeing. If you Google "absolute vs. gauge pressure" you can probably find a better explanation than I can provide.

  11. #71
    I understand, but why would the desired boost be 30 psi. Wouldn?t it desire 15 psi. Or does the desired boost take into account the atmospheric pressure.

  12. #72
    Tuner
    Join Date
    Jul 2019
    Location
    Wilmington, MA, USA
    Posts
    71
    Quote Originally Posted by 1970ss8.1 View Post
    Or does the desired boost take into account the atmospheric pressure.
    Yep, it does!

    You and I tend to think of manifold pressure (= boost) as vacuum/pressure relative to atmosphere. But engines function mostly in terms of absolute pressure, so that's what they use for boost control.

  13. #73
    What would cause me to be commanding 2.00 lambda when I let off the petal. Shouldn?t it be 1.00

  14. #74
    Tuner
    Join Date
    Sep 2019
    Location
    ON, Canada
    Posts
    84
    Decel enleanment/cutoff

  15. #75
    Thanks Ill look into that. Ive been working on the scanner setting up some good tables. Take a look and see if im on the right track.
    Attached Files Attached Files
    My Avatar is my Wife and Proud of it!!
    1970 Chevelle SS 8.1 Vortec T56 9" 3.00
    2006 3500HD 8.1 vortec Allison 6sp 4.10 4X4
    2013 Audi A5 Cab 2.0tfsi Quatro
    www.mcmnapa.com