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Introduction

The EA888 Gen 3 (EA888.3) is a global engine suitable for MLB (Modularer Langsbaukasten/Longitudinal ) and MQB (Modularer Querbaukasten/Transverse) platforms, capable of meeting the latest emission and fuel economy targets in different markets

In the Europe, the new MQB EA888 Gen 3 engines were introduced to Volkswagen Golf, Skoda Octavia, Seat Leon and Audi A3/S3 vehicles.  These engines were partnered with a 6 speed manual or the DQ250 6 speed DSG gearbox.

The 6 Speed DSG transmission has two wet clutches bathed using concentric friction disks and clutch plates.  like other gearboxes once clutch is drives odd gear, the other drives even gears.  Clutch clamping force is delivered by clutch pressure which in turn is which is converted to duty cycle and controlled by solenoid current.

Clutch pressure is controlled in full time closed loop, while clutch pressure targets are set primarily by torque demand sent from the ECM.  The DQ250 transmissions are known to hold slightly less torque that the later DQ381 7 speed gearboxes and in stock form the torque is limited by the controller to around 350Nm in some calibrations. The physical limits of the transmission are not known with particular detail but the clutch patch appear to slip before the gearset breaks.

The DQ250 has different drive modes, the main 3 modes are Drive (normal), Sport, and Tiptronic (TT). Depending on the vehicle configuration, there may be additional modes available, such as ECO (Economy), and ALT (High Altitude).

  • Drive and Sport modes are the main influence on current gear choice. In these modes the DSG will choose the correct gear based upon

    • Axle torque

    • Throttle position

    • Engine RPM

    • Recent driving behavior / timed behavior changes. 

  • Tiptronic Function (manual shifting) - Is selected using the factory paddles or by placing the shifter in the manual shifting (Tiptronic) position.  Within each of these drive modes there are more tables and logic to further define their function.

Each file seeks to address:

  • No forced KD in manual mode.

  • No forced KD in lower gears.

  • Increased LC rev limit using TCU setpoint.

  • Manual shift in LC.

  • Tweak on shift routines.

  • Tweak on shift times.

  • Tweak on shift torque reduction times.

  • Increased clamp pressure at full load engine torque.

  • Revised kiss point.

  • Option to run LC wit ESP on in manual mode

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