Isuzu 2008MY N Series, Руководство по ремонту

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Engine Control System (4HK1) 1A-385
Fuel System Description
The common rail system uses a type of accumulator
chamber called the fuel rail to store pressurized fuel,
and injectors that contain electronically controlled
solenoid valves to spray the pressurized fuel in the
combustion chambers. The injection system (injection
pressure, injection rate, and injection timing) is
controlled by the ECM, and therefore the common rail
system can be controlled independently, free from the
influence of engine speed and load. This ensures a
stable injection pressure at all time, particularly in the
low engine speed range, so that black smoke specific
to diesel engines generated during vehicle starting or
acceleration can be reduced dramatically. As a result,
exhaust gas emissions are clear and reduced, and
higher output is achieved.
1. High Pressure Control
• Enables high pressure injection from low engine
speed range.
• Optimizes control to minimize particulate matter
and NOx emissions.
2. Injection Timing Control
• Enables finely tuned optimized control in
accordance with running conditions.
3. Injection Rate Control
• Pilot injection control that performs a small amount
of injection before main injection.
The fuel rail system consists primarily of a fuel supply
pump, fuel rail, injectors, and ECM.
LNW76EMF000601
Supply pump
Fuel filter
Fuel tank
Camshaft
position
sensor
Crankshaft
position
sensor
Various sensors
(accelerator position sensor, coolant temperature,
mass air flow, etc.)
Injectors
Pressure sensor
Fuel rail
Pressure
limiter valve
ECM
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