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MEC990D
ENGINE AND EMISSION CONTROL OVERALL SYSTEMZD30DDTi
Engine Control Component Parts Location
(Cont'd)EC-14
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MEC029E
ENGINE AND EMISSION CONTROL OVERALL SYSTEMZD30DDTi
Engine Control Component Parts Location
(Cont'd)EC-15
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Circuit Diagram
YEC662A
ENGINE AND EMISSION CONTROL OVERALL SYSTEMZD30DDTi
EC-16
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System Diagram
SEC390D
ENGINE AND EMISSION CONTROL OVERALL SYSTEMZD30DDTi
EC-17
http://vnx.su/
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Vacuum Hose Drawing
1. Swirl control valve control solenoidvalve to swirl control valve actua-
tor
2. Intake air control valve control solenoid valve to intake air control
valve actuator 3. Variable nozzle turbocharger con-
trol actuator to vacuum damper
4. Variable nozzle turbocharger con- trol solenoid valve to resonator 5. Variable nozzle turbocharger con-
trol solenoid valve to vacuum
pump
Refer to ªSystem Diagramº, EC-17 for vacuum control system.
MEC030E
ENGINE AND EMISSION CONTROL OVERALL SYSTEMZD30DDTi
EC-18
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System Chart
Input (Sensor)ECM FunctionOutput (Actuator)
I Electronic control fuel injection pump
I Crankshaft position sensor (TDC)
I Engine coolant temperature sensor
I Accelerator position sensor
I Accelerator position switch
I Accelerator switch (F/C)
I Park/Neutral position (PNP) switch
I Ignition switch
I Battery voltage
I Vehicle speed sensor
I Air conditioner switch
I Mass air flow sensor
I Stop lamp switch
I Heat up switch
I Charge air pressure sensor*1 Fuel injection control
Electronic control fuel injection pump
Fuel injection timing control Electronic control fuel injection pump
Fuel cut control Electronic control fuel injection pump
Glow control system Glow relay & glow lamp
On board diagnostic system MI (On the instrument panel)
EGR volume control EGR volume control valve
Cooling fan control Cooling fan relay
Air conditioning cut control Air conditioner relay
Variable nozzle turbocharger control Variable nozzle turbocharger control sole- noid valve
Swirl control valve control Swirl control valve control solenoid valve
Intake air control valve control Intake air control valve control solenoid
valve
*1: This sensor is not used to control the engine system under normal conditions.
ENGINE AND EMISSION CONTROL OVERALL SYSTEMZD30DDTi
EC-19
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Fuel Injection Control System
DESCRIPTION
System description
Three types of fuel injection control are provided to accommodate engine operating conditions; normal control,
idle control and start control. The ECM determines the appropriate fuel injection control. Under each control,
the amount of fuel injected is compensated to improve engine performance.
Pulse signals are exchanged between ECM and electronic control fuel injection pump (control unit is built-in).
The fuel injection pump control unit performs duty control on the spill valve (built into the fuel injection pump)
according to the input signals to compensate the amount of fuel injected to the preset value.
Start control
Input/output signal chart
SensorInput Signal to ECM ECM Function Actuator
Engine coolant temperature sensor Engine coolant temperature
Fuel injection con-
trol (start control)Electronic control fuel injec-
tion pump
Crankshaft position sensor (TDC)
Engine speed
Ignition switch Start signal
When the ECM receives a start signal from the ignition switch, the
ECM adapts the fuel injection system for the start control. The
amount of fuel injected at engine starting is a preset program value
in the ECM. The program is determined by the engine speed and
engine coolant temperature.
For better startability under cool engine conditions, the lower the
coolant temperature becomes, the greater the amount of fuel
injected. The ECM ends the start control when the engine speed
reaches the specific value, and shifts the control to the normal or
idle control.
Idle control
Input/output signal chart
SensorInput Signal to ECM ECM Function Actuator
Engine coolant temperature sensor Engine coolant temperature
Fuel injection con-
trol (Idle control)Electronic control fuel injec-
tion pump
Crankshaft position sensor (TDC)
Engine speed
Park/Neutral position (PNP) switch Gear position
Battery Battery voltage
Accelerator position switch Idle position
Vehicle speed sensor Vehicle speed
Air conditioner switch Air conditioner signal
Heat up switch Heat up switch signal
When the ECM determines that the engine speed is at idle, the fuel injection system is adapted for the idle
control. The ECM regulates the amount of fuel injected corresponding to changes in load applied to the engine
to keep engine speed constant. The ECM also provides the system with a fast idle control in response to the
engine coolant temperature and heat up switch signal.
SEF648S
ENGINE AND EMISSION BASIC CONTROL SYSTEM
DESCRIPTIONZD30DDTi
EC-20
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Normal control
Input/output signal chart
SensorInput Signal to ECM ECM Function Actuator
Crankshaft position sensor (TDC) Engine speed
Fuel injection con-
trol (Normal con-
trol)Electronic control fuel injec-
tion pump
Accelerator position sensor
Accelerator position
Vehicle speed sensor Vehicle speed
The amount of fuel injected under normal driving conditions is
determined according to sensor signals. The crankshaft position
sensor (TDC) detects engine speed and the accelerator position
sensor detects accelerator position. These sensors send signals to
the ECM.
The fuel injection data, predetermined by correlation between vari-
ous engine speeds and accelerator positions, are stored in the
ECM memory, forming a map. The ECM determines the optimal
amount of fuel to be injected using the sensor signals in compari-
son with the map.
Maximum amount control
Input/output signal chart
SensorInput Signal to ECM ECM Function Actuator
Mass air flow sensor Amount of intake air
Fuel injection con-
trol (Maximum
amount control)Electronic control fuel injec-
tion pump
Engine coolant temperature sensor Engine coolant temperature
Crankshaft position sensor (TDC) Engine speed
Accelerator position sensor Accelerator position
The maximum injection amount is controlled to an optimum by the engine speed, intake air amount, engine
coolant temperature, and accelerator opening in accordance with the driving conditions.
This prevents the oversupply of the injection amount caused by decreased air density at a high altitude or
during a system failure.
Deceleration control
Input/output signal chart
Sensor
Input Signal to ECM ECM Function Actuator
Accelerator switch (F/C) Accelerator positionFuel injection con-
trol (Deceleration
control)Electronic control fuel injec-
tion pump
Crankshaft position sensor (TDC) Engine speed
The ECM sends a fuel cut signal to the electronic control fuel injection pump during deceleration for better
fuel efficiency. The ECM determines the time of deceleration according to signals from the accelerator switch
(F/C) and crankshaft position sensor (TDC).
SEF649S
ENGINE AND EMISSION BASIC CONTROL SYSTEM
DESCRIPTIONZD30DDTi
Fuel Injection Control System (Cont'd)
EC-21
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