Nissan Note [1614/1872] Ec 1614

Nissan Note [1614/1872] Ec 1614
EC-1614
[K9K]
ENGINE CONTROL SYSTEM
Charge air pressure
Intake air temperature
Charge air pressure
Engine coolant temperature
Fuel rail pressure
Ambient barometric pressure
The quantities to be injected and their respective advances are converted into:
Reference tooth
Time between this tooth and the start of the pulse
Time for which the fuel injector holder is fed
An electrical current (pulse) is sent to each fuel injector holder as a function of the previously calculated data.
The system performs between one and four injections (a pilot injection, a pre-injection, a main injection and a
post-injection). The general principle is to calculate a total delivery injected which will then be distributed
across the deliveries of the various injections to promote efficient combustion and a reduction in pollutant
emissions.
A knock sensor is used to control some of the deviations when the fuel is injected. This plays a number of
roles:
Protection of the engine by detecting injection losses (disabled on the basic version)
Checking of the pilot quantity by measurement of the deviations and dispersions
By modifying the duration on the one hand and the injection advance on the other, it is possible to readjust the
quantity of fuel injected and the instant of ignition of the mixture.
FUEL RAIL PRESSURE CONTROL
The quality of combustion is influenced by the size of the droplets atomised in the cylinder. In the combustion
chamber, smaller drops of fuel will have time to burn completely and not produce smoke or nonburned parti-
cles. To meet anti-pollution requirements it is necessary to reduce the size of the droplets and thus the injec-
tion holes.
The smaller these holes are, the less fuel can be introduced at a given pressure which limits the power. To
overcome this malfunction it is necessary to increase the quantity of fuel injected which in practice means
increasing the pressure (and the number of openings of the fuel injector nozzles). In the case of the Delphi
Common Rail, the pressure can reach 1600 bar in the fuel rail and must be permanently controlled. The mea-
surement circuit is comprised an active fuel rail pressure sensor on the fuel rail linked to an analogue port of
the ECM.
The high-pressure pump is fed at low pressure (5 bar) by an integral transfer pump. This feeds the fuel rail, the
pressure of which is controlled for the charging by the fuel flow actuator (fuel pressure regulator) and for dis-
charge by the fuel injector. This allows drops in pressure to be compensated. The fuel flow actuator (fuel pres-
sure regulator) allows the high-pressure pump to only supply the quantity of fuel necessary to maintain the
pressure in the fuel rail. Thanks to this device, the generation of heat is minimised and the efficiency of the
engine is improved.
In order to discharge the fuel rail using the fuel injectors, the fuel injectors are operated by means of small
electrical pulses:
Sufficiently small not to open the fuel injector (the fuel passes through the return circuit from the fuel injec-
tors)
Sufficiently long to open the valves and discharge the fuel rail
Surplus fuel is fed back to the fuel filter or to the reservoir according to its delivery. In the event of non-actua-
tion of the fuel flow actuator (fuel pressure regulator), the pressure in the fuel rail is limited by a pressure relief
valvefittedonthepump.
IDLING CONTROL
The ECM is responsible for idling control. In practice it has to take into account the instantaneous power level
to be delivered as a function of the following elements:
Engine coolant temperature

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