Operation Section
1
–
72
(5) Fuel Injection Timing Control
• The fuel injection timing is controlled by the timing of the current applied to the injectors. After the main injection period
is decided, the pilot injection and other injection timing is determined.
Main Injection Timing
- The basic injection timing is calculated from the engine speed (engine speed pulse) and the final injection quantity,
to which various types of corrections are added in order to determine the optimal main injection timing.
Pilot Injection Timing (Pilot Interval)
- Pilot injection timing is controlled by adding a pilot interval value to the main injection. The pilot interval is calculated
based on the final injection quantity, engine speed, coolant temperature, atmospheric temperature, and atmospher-
ic pressure (map correction). The pilot interval at the time the engine is started is calculated from the coolant tem-
perature and engine speed.
Q000896E
Actual Top Dead Center
Pilot Injection
Main Injection
Pilot Injection Timing
Pilot Interval
Main Injection Timing
1. Outline of Injection Timing Control Timing
2. Injection Timing Calculation Method
Engine Speed
Injection Quantity
Basic Injection
Timing
Correction
Main
Injection Timing
Battery Voltage Correction
Intake Air Pressure Correction
Atmospheric Pressure Correction
Intake Air Temperature Correction
Coolant Temperature Correction
Pilot Interval
Basic Injection
Timing
Pilot Interval
Engine Speed
Basic Injection Timing
Pilot
Injection Timing
NE
INJ
lift
1
0
Engine Speed
Engine Speed
Pulse
Injector Solenoid Valve
Control Pulse
Nozzle Needle
Lift
To Next Page
Loading...
