PGM-FI System Description - Injection Control
Fuel injection controls include fuel injection amount control, fuel cut control and fuel pump control. Adopting PGM-FI (programmed-fuel injection) technology enables accurate fuel controls, which contributes to increased engine power and decreased fuel consumption.
Fuel Injection Amount
The fuel injection amount is determined by adding correction values to a basic injection amount.
The PCM controls the amount of fuel injection by the length of time the injector is energized.
Fuel Injection Timing
The fuel injection timing is determined by the PCM, which calculates the injection time for each cylinder based on the signals sent from the crankshaft position (CKP) sensor and the camshaft position (CMP) sensor. The PCM then controls the time to energize the injector.
In addition, the fully sequential injection system is adopted as a fuel injection system.
CKP Sensor
The CKP sensor is attached to the cylinder block. When each of the 58 teeth on the CKP pulse plate passes over it, a pulse signal is delivered to the PCM.
CMP Sensor B
The camshaft position (CMP) sensor B is attached to the cylinder head. Every time one of the three protrusions of the pulse plate attached to the camshaft passes over it, a pulse signal is delivered.
Injector
The injector for a gaseous fuel supply has multiple holes. A nozzle with multiple holes increases the fuel atomization and improves the mixing with the surrounding air.
When the coil in the injector is energized, the plunger is pulled in. The needle valve, which is integral with the plunger, is pulled fully. Then, the injector sprays the pressurized fuel which is controlled by the fuel pressure regulator.
MAF Sensor/IAT Sensor 1
The mass air flow (MAF) sensor/intake air temperature (IAT) sensor 1 contains a hot wire, a cold film, and a thermistor. The sensor is in the intake air passage. The resistance of the hot wire, the cold film, and thermistor changes due to intake air temperature and air flow. The control circuit in the MAF sensor controls the current to keep the hot wire at a set temperature. The current is converted to voltage in the control circuit, then sent as an output to the PCM.