Contents: Air Conditioner (A/C) Clutch Relay ⇊ Air to Fuel Ratio (A/F) Sensor ⇊ Barometric pressure sensor (BARO) ⇊ Camshaft Position (CMP) Sensor ⇊ Crankshaft position sensor (CPS) ⇊ Coolant Temperature Sensors 1 and 2…⇊
The Programmed Multi-Point Fuel Injection (PGM-FI) system is a sequential, multi-point fuel injection system.
Air Conditioner (A/C) Clutch Relay
When the ECM receives a command to turn on the air conditioner, it delays power to the air conditioner compressor for a period of time and enriches the mixture to provide a smooth transition to air conditioner-on operation.
Air to Fuel Ratio (A/F) Sensor
The A/F sensor operates over a wide range of air-fuel mixtures. The A/F sensor is mounted upstream of the three-way catalytic converter (TWC) and sends signals to the ECM/PCM, which adjusts the fuel injection duration accordingly.
Barometric pressure sensor (BARO)
The BARO sensor is installed inside the ECM. It converts the atmospheric pressure value into a voltage signal, which adjusts the basic duration of the fuel injection process.
Camshaft Position (CMP) Sensor
The CMP sensor detects the position of cylinder #1 as a reference to control sequential fuel injection into each cylinder.
Crankshaft position sensor (CPS)
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The CKP sensor determines the crankshaft speed, ignition timing and the start of fuel injection for each cylinder, and also determines combustion misfires in the engine cylinders.
Coolant Temperature Sensors 1 and 2 (ECT)
Sensors ECT 1 and 2 are a resistor that changes its resistance depending on the temperature (thermistor). Resistance decreases as engine coolant temperature increases.