Diesel Engine Control System – Types of Sensor

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Engine Speed Sensor
The engine speed sensor is fitted in the injection pump. It consist of a rotor that is pressed over a drive shaft, and a sensor. Electric signals are generated in the sensor (coil) in accordance with the rotation of the rotor.
Engine Speed Sensor
Here is the relationship between the rotation of the rotor and the generated waveform. The ECU counts the number of pulses to detect theengine speed. The rotor makes half a revolution for each revolution of the engine. The ECU detects the reference angle from the missing tooth portion, which is located along the cicumference of the rotor.
Engine Speed Sensor
The 1CD-FTV common-rail EFI-diesel engine uses the crankshaft position sensor to detect the engine speed just as in the EFI system of a gasoline engine, in place of the engine speed sensor used in a conventional EFI-diesel engine. The crankshaft position sensor of the common-rail EFIdiesel engine outputs the same NE signal that is output by the engine speed sensor of the conventional EFI-diesel engine.
Crankshaft Position Sensor
The crankshaft position sensor is mounted on the engine block. It detects the crankshaft angle reference position in the form of a TDC signal. HINT: The crankshaft position sensor of common-rail type output the engine speed (NE) signals. It detects the crank angle based on these NE signals. A pulse is generated when the protrusion provided on the crankshaft padded near the sensor due to the revolution of the crankshaft. A pulse is generated once for every revolution of the crankshaft, and this is detected in the form of a crankshaft angle reference position signal.
Camshaft Position Sensor
A camshaft position sensor is used on some engines (1CD-FTV) in place of a crankshaft angle reference position is detected in the form of a G signal.
1ND-TV Engine
For the 1ND-TV engine a hall element type camshaft position sensor is used. The timing trigger on the timing sprocket detects the position of the camshaft by sending one signal for every two revolutions of the crankshaft.
Turbo Pressure Sensor
The turbo pressure sensor is connected to the intake manifold via an air hose and a VSV, and detects the intake manifold pressure (intake air volume).

REFERENCE
Turbo Pressure Sensor
The VSV operates in accordance with the signals form the ECU and switched the pressure that is applied to the actuator between atmosphere and vacuum. Vacuum Atmosphere
Water Temperature/Intake Air Temperature/ Fuel Temperature Sensor
There are three types of temperature sensors that are used for controlling the EFI-diesel:
The water temperature sensor is mounted on the engine block to detect the temperature of the engine coolant. The intake air temperature sensor is mounted on the intake pipe of the engine and detects the temperature of the intake air. The fuel temperature sensor is mounted on the pump and detects the temperature of the fuel. Each type of temperature sensor has a built-in thermistor whose resistance varies in accordance with the temperature and its characteristics are as indicated in the diagram.
Fuel Pressure Sensor
The fuel pressure sensor that is used in the common-rail type diesel detects the fuel pressure in the common-rail. Based on the signals from the fuel pressure sensor, the ECU controls the SCV (Suction Control Valve) to generate a prescribed fuel pressure in accordance with the driving conditions.
Air Flow Meter
A hot-wire type air flow meter has been adopted in the common-rail EFI-diesel to detect the intake air volume.

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