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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 Duration 

The fuel injection duration is determined by adding correction values to a basic injection duration. The powertrain control module (PCM) controls the amount of fuel injection by the length of time the injector is energized.

GHH118011Courtesy of HONDA, U.S.A., INC.

Fuel Injection Timing 

The fuel injection timing is determined by the PCM, which calculates the injection time for each cylinder based on the signals 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, CMP Sensor 

The CKP sensor is attached to the cylinder block. Each of the 58 teeth on the CKP pulse plate passes over it, a pulse signal is delivered to the PCM. The CMP sensor is attached to the cylinder head. Every time one of the three protrusions of the CMP pulse plate attached to the camshaft passes over it, a pulse signal is delivered.

GHH118012Courtesy of HONDA, U.S.A., INC.
GHH118013Courtesy of HONDA, U.S.A., INC.

Fuel Injector 

The fuel injector for fuel supply has multiple holes. A nozzle with multiple holes increases 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.

GHH118014Courtesy of HONDA, U.S.A., INC.

MAF Sensor/IAT Sensor 

The mass air flow (MAF) sensor/intake air temperature (IAT) sensor 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 the 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 input to the PCM.

GHH118015Courtesy of HONDA, U.S.A., INC.