ICP Injection control pressure sensor
Feedback input. The PCM monitors the high pressure oil system to determine if it needs to be increased if load demand increases. It also uses this to stabilize idle speed. Volts in: 1.0 volt @ 580 psi, 3.22 volts @ 2520 psi.
IPR injection pressure regulator
Output. The PCM controls the high pressure oil system by varying the duty cycle of the IPR. The IPR controls the oil bypass circuit of the high pressure pump. 0% = full return to sump (open valve), 100% = full flow to injectors (closed valve). The PCM monitors the system with the ICP input. The PCM can control fuel delivery to the injectors by increasing the IPR duty cycle which increases fuel pressure through the injector nozzles.