Injection Control Pressure (ICP) Sensor
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The ICP sensor is a variable capacitor sensor that is supplied a 5-volt reference signal by the PCM and returns a linear analog voltage signal that indicates pressure. The sensor measures the oil pressure in the oil rail and the PCM uses this information to determine injection control pressure. The ICP sensor along with the injection pressure regulator (IPR) form a closed loop fuel pressure control system.
If the PCM detects an inoperative ICP sensor, the PCM controls the injection control pressure from a PCM estimated injection control pressure.