Conditions for Setting the DTC
P0191 - Condition 1
The difference between the low side fuel pressure and the high side fuel pressure is less than or equal to -1 MPa (-145 PSI) or greater than or equal to 1 MPa (145 PSI) with the high pressure fuel pump actuator commanded OFF. The condition exists for greater than 3 s.
P0191 - Condition 2
The difference between the relief pressure and the measured high pressure is less than or equal to -1.6 MPa (-232 PSI) with the high pressure fuel pump actuator commanded ON. The condition exists for greater than 2 s.
P0191 - Condition 3
The difference between the commanded high pressure and the measured high pressure is greater than or equal to 3 MPa (435 PSI) and the modeled injection pressure is greater than or equal to 1.6 MPa (232 PSI) with the high pressure fuel pump actuator commanded ON. The condition exists for greater than 3 s.
P0191 - Condition 4
The difference between the measured maximum high pressure and the measured minimum high pressure is less than or equal to 0.1 MPa (14.5 PSI) with the high pressure fuel pump actuator commanded ON. The condition exists for greater than 30 s with the engine running or greater than 10 s with the engine cranking.
P0192
The ECM detects that the fuel rail fuel pressure sensor signal voltage is low for greater than 5 s.