* follow the advice in the funktionsrahmen and set the values in LDRXNZK a bit lower than LDRXN. Em média o LDRXNZK é 15% menor que o LDRXN
* KFLDHBN (LDR-Höhenbegrenzung max. Verdichterdruckverhältnis, charge pressure control: upper limit [compressor pressure ratio]). Units (x,y,z): °C, RPM, ratio
- Remarks: the S4 wiki notes that on a WOT run, the charge profile will follow LDRXN but because K03 and K04 turbochargers have significant flow limitations, unlike big turbochargers, charge pressure should peak before the engine speed limit then taper off. The compressor map for these turbochargers is shown in Figure 5.1. The ECUxPlot software has a pressure ratio/flow plotter that can be used use to compare against a turbo’s compressor map. The DTC 17963 “Charge pressure: Maximum limit exceeded” will result if boost deviation is too high. There is no difference between the BAM & BFV maps for charge pressure upper limit (compressor pressure ratio).
KFDLULS (Delta Druck für Überladeschutzdiagnose, pressure change for overboost protection diagnosis). Units (x,y,z): mbar, RPM, mbar
- Remarks: The S4 wiki notes that if charge pressure is significantly higher than stock, or changes have been made to the boost PID control parameters, then consideration should be given to increasing these limits to avoid overboost protection activating at too low a threshold. The most unsophisticated way would be to simply set all the values in the table to maximum but since this will short-circuit an important safety feature, it is better to spend time iterating and optimizing appropriate values.
KRKTE - is the constant for converting a reference load in % into fuel injection open time ms. So the units for this value are ms/%. The ecu calculates a reference load % based on the desired AFR. If the ecu wants to run rich, the reference load is higher than the actual load. If the ecu wants to run lean, the reference load is lower than the actual load. If the ecu wants to run at stoich, then the reference load is the same as the actual load. So if the reference load was 100% then the injection time would be KRKTE * 100. If you increase the size of your injectors, or increase your fuel pressure you need to scale this number down. If you decrease the size of your injectors, or decrease your fuel pressure you need to scale this number up.
MLHFM - is the table for converting MAF voltage in volts into air mass in grams/second. It should be a 1x512 map in the B5 S4. If you increase the size of your MAF housing you will need to scale this map up, and if you decrease the size of your MAF housing you will need to scale this value down.
TVUB - injection time offset based on voltage
TVTSPEV - injection time offset based on estimated injector temperature
FRLFSDP - injection time scaling factor based on predicted vacuum relative to outside pressure
