General Information

Engine Control
P0191 Fuel Rail Pressure Sensor Circuit Range/Performance - General Information

Component Location





General Description

The Low Pressure Pump (LPP) supplies 65 psi(4.5 bar) of fuel pressure to the High Pressure Pump (HPP).
Using the internally located Fuel Pressure Regulator Valve (FPR), the HPP will boost the fuel pressure from 580 psi(40 bar) at idle to a maximum of 1958 psi(135 bar).
The Fuel Pressure Sensor (FPS) confirms the fuel pressure and returns the signal to the Powertrain Control Module (PCM).
Fuel pressure during limp-home mode is 65 psi(4.5 bar).

DTC Description

P0191 is set when the Fuel Pressure Signal is too high or low.

DTC Detecting Condition





Specification





Diagnostic Circuit Diagram





Signal Waveform & Data




- Fuel Pressure rises with rapid increase in RPM.




- Fuel Pressure Signal and Power Supply Voltage of Fuel Pressure Sensor at Idle.




- Sample: P0191 setting when the Signal Voltage of Fuel Pressure Sensor is Abnormally Low.




- Sample: P0191 setting when the Signal Voltage of Fuel Pressure Sensor is Abnormally High.