Tuning

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Revision as of 19:27, 30 August 2009 by Nyet (talk | contribs) (→‎References)
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Getting Started

Things you need

  1. KWP2000+ OBD cable
  2. KWP2000+ flashing software
  3. TunerPro
  4. XDF file for the revision of ECU you are using. If you wish to use a different version software than your car came with, read this carefully.
  5. ECUFix (optional, some kwp flashing software will do checksumming for you)

Fueling

  • KRKTE - primary fueling
  • KVB - fuel consumption (MPG in cluster)
  • MLHFM - compensating for MAF housing diameter
  • KFLDBTS - requested lambda for component protection when calculated EGT is above TABGBTS (may require a lower TABGBTS if your MAF is not 100% compensated for in MLHFM)
  • LAMFA - requested lambda when calculated EGT is below TABGBTS

Boost

  • KFMIRL - specified load
  • FLKDHBN - maximum requested pressure ratio
  • LDRXN - maximum specified load
  • KFTARX - IAT correction for maximum specified load

Cam changeover affect on requested boost

Motronic likes to change requested boost depending on cam position. While it may seem like a good idea in theory, in practice, abrupt changes in requested boost near the MAP limit can make the boost PID unhappy. When logging, you may see an odd notch in requested boost between 3000 and 4000 RPM. These maps are what is causing that notch

  • KFPBRK - Correction factor for combustion chamber pressure
  • KFPBRKNWS - Correction factor for combustion chamber pressure when NWS active
  • KFPRG - Internal exhaust partial pressure dependent on cam adjustment when sumode=0
  • KFURL - Conversion constant for ps->rl dependent on cam adjustment when sumode=0

Timing

  • KFZW/KFZW2 - primary timing maps. ME7.1 has a two point variable cam timing system; there is a table for each cam timing state. When running elevated boost, you will have to significantly cut requested timing to prevent timing retard. Keep your worst case correction factors in the single digits, and always carefully monitor your knock voltages when tuning your timing.

Other niceties

Speed limiter

  • VAVMX/VMAX - Speed limiter

Rev limiter

  • NMAX - RPM limit
  • NLLM - idle RPM

Left foot braking

Set either of these to maximum to prevent throttle cut when left foot braking:

  • NWPMBBR - Minimum RPM for acc pedal value lockout on brake operation
  • VWPMBBR - Minimum speed for acc pedal value lockout on brake operation

Knock control

Launch control

Emissions

  • CDKAT - Cat diagnosis in OBDII-Mode. Set to zero to disable rear cat DTC

References

Motronic abbreviations