Alpha-N With Map Multiplication; Corrections - ECU Master EMU User Manual

ALPHA-N with MAP multiplication

Algorithm combining features of Speed Density and Alpha-N. The load is defined by TPS, while VE
value is multiplied by the value of absolute pressure in the intake manifold. It can be used for both
naturally aspirated and turbocharged engines.
PW = INJ_CONST * VE(tps,rpm) * MAP * AirDensity * Corrections + AccEnrich +
InjOpeningTime
PW (pulse width)
INJ_CONST
VE(tps, rpm)
MAP
AirDensity

Corrections

AccEnrich
InjOpeningTime
Corrections
Corrections = Baro * Warmup * ASE * EGO * KS * NITROUS
Corrections
Baro(barometric correction) Barometric correction used in Alpha-N algorithm
Warmup(warmup
enrichment)
ASE(Afterstart enrichment) Enrichment applied after engine start for given number of engine
EGO(Exhaust gas oxgen
sensor correction)
KS(Knock Sensor
Correction)
NITROUS
final time of injector's opening
a constant for the given size of injectors, engine's displacement,
pressure 100kPa, temperatures of the intake air 21°C, VE 100%,
time of injectors' opening required to obtain the stoichiometric
mixture (Lambda = 1)
value of volumetric effectiveness read from the VE table
Intake manifold pressure
percentage difference of air density towards air density in
temperature 21°C
fuel dose corrections (discussed in the following pages)
acceleration enrichment
the time it takes for an injector to open from the time it has been
energized until it is fully open (value from the calibration map
Injectors cal.)
Final percentage value of fuel dose correction
value of mixture enrichment in the function of cooling liquid
temperature expressed in percentage
cycles
correction according to indications of the Lambda probe
enrichment in the moment of knock occurrence
enrichment of the mixture with the activation of nitrous oxide system
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