P0088
DTC P0088 Fuel Rail / System Pressure - Too HighDESCRIPTION
DTC Detection Condition:
The cylinder fuel injection method high-pressure fuel system consists of the spill control valve, pump plunger and check valve. The spill control valve adjusts the discharge amount of the high-pressure fuel, the pump plunger operated by the camshaft pressurizes fuel, the check valve mechanically opens and closes the line to the fuel delivery pipe. The fuel pump for high pressure is installed to the cylinder head cover (bank 1 and bank 2) and is driven by the cam located at the rear end of the intake camshaft. When the plunger moves up and down by the camshaft rotations, it pressurizes the fuel. The pressurized fuel then pushes open the check valve, and the fuel flows to the fuel delivery pipe. The ECM controls the spill control valve to adjust the fuel pressure to 4 to 13 MPa (41 to 133 kgf/sq.cm). The ECM receives signals from the fuel pressure sensor, monitors the fuel pressure, and maintains the target fuel pressure. If the fuel pressure of the fuel delivery pipe exceeds 15.3 MPa (156 kgf/sq.cm), the fuel relief valve opens and returns the fuel to the fuel tank.
MONITOR DESCRIPTION
Monitor Strategy:
Typical Enabling Conditions:
Typical Malfunction Thresholds:
If the fuel pressure does not decrease even after the ECM commands the high-pressure fuel pump to open the spill control valve, a DTC is output.
If there is minimal difference between the fuel pressure before and after the fuel relief valve operates, a DTC is output.
Step 1:
Step 1(Continued)-3:
Step 3(Continued)-7:
Step 7(Continued):
INSPECTION PROCEDURE
HINT: Read freeze frame data using the intelligent tester or Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.