P0087

1UR-FSE ENGINE CONTROL SYSTEM: SFI SYSTEM: P0087: Fuel Rail / System Pressure - Too Low

DTC P0087 - Fuel Rail / System Pressure - Too Low

DESCRIPTION

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/cm2). 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/cm2), the fuel relief valve opens and returns the fuel to the fuel tank.









MONITOR DESCRIPTION

If the fuel pressure decreases even after the ECM commands the high-pressure fuel pump to close the spill control valve, a DTC is output.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS





TYPICAL MALFUNCTION THRESHOLDS





INSPECTION PROCEDURE
HINT: Read freeze frame data using the Techstream. The ECM records vehicle and driving condition information as freeze frame data the moment a DTC is stored. When troubleshooting, freeze frame data can be helpful in determining whether the vehicle was running or stopped, whether the engine was warmed up or not, whether the air fuel ratio was lean or rich, as well as other data recorded at the time of a malfunction.

PROCEDURE

1. CHECK FUEL LEAK (HIGH PRESSURE SIDE)
(a) Check around and beneath the car for gasoline leaks, fumes, etc.
OK:
No gasoline leaks present.
NG -- REPAIR OR REPLACE FUEL LEAK POINT
OK -- Continue to next step.

2. CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTC P0087)
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG) and turn the Techstream ON.
(c) Enter the following menus: Powertrain / Engine / Trouble Codes.
(d) Read the DTCs.
Result:





HINT: If any DTCs other than P0087 are output, troubleshoot those DTCs first.

B -- GO TO DTC CHART
A -- Continue to next step.

3. CHECK FUEL PRESSURE SENSOR (LOW PRESSURE)
(a) Check the fuel pressure Testing and Inspection.
NG -- REPLACE FUEL PUMP ASSEMBLY (for Low Pressure)
OK -- Continue to next step.

4. CHECK MISFIRE COUNT
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG) and turn the Techstream ON.
(c) Start the engine.
(d) Enter the following menus: Powertrain / Engine / Active Test / Control the Injection Way / Direct.
(e) Allow the engine to idle.
(f) Monitor all of the misfire rate values that are displayed on the Techstream: Powertrain / Engine / Data List / Misfire / Cylinder #1 Misfire rate to Cylinder #8 Misfire rate.
If no misfire counts occur for any of the cylinders, perform the following procedure:
(1) Move the shift lever to the D position.
(2) Monitor all of the misfire rate values that are displayed on the Techstream.
Result:






B -- REPLACE FUEL INJECTOR FOR DIRECT INJECTION
A -- Continue to next step.

5. INSPECT FUEL RELIEF VALVE
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG) and turn the Techstream ON.
(c) Start the engine.
(d) Enter the following menus: Powertrain / Engine / Data List / Fuel Press.
(e) Write down the FUEL PRESS (Fuel Press) value.
(f) Turn the engine switch off.
(g) Wait for 10 seconds.
(h) Turn the engine switch on (IG) and turn the Techstream ON.
(i) Enter the following menus: Powertrain / Engine / Data List / Fuel Press.
(j) Compare the Fuel Press value and the fuel pressure value after the engine switch was turned on (IG).
Result:






B -- REPLACE FUEL RELIEF VALVE
A -- Continue to next step.

6. CHECK FUEL PRESSURE SENSOR (HIGH PRESSURE)
(a) Check the fuel pressure Testing and Inspection.
NG -- REPLACE FUEL PUMP ASSEMBLY (for High Pressure)
OK -- Continue to next step.

7. INSPECT INJECTOR DRIVER (NO. 1 AND NO. 2)
(a) Turn the engine switch off.




(b) Replace the No. 1 and No. 2 injector drivers with known good ones.
NOTE:
Do not disconnect and reconnect the connectors with the engine switch on (IG), as the injector driver (EDU) may be damaged.
(c) Connect the Techstream to the DLC3.
(d) Start the engine.
(e) Clear the DTCs DTC Check / Clear.
(f) Perform the driving test.
(g) Enter the following menus: Powertrain / Engine / Trouble Codes.
(h) Read the DTCs.

Result





B -- REPLACE INJECTOR DRIVER (NO. 1 AND NO. 2)
A -- Continue to next step.

8. REPLACE FUEL PUMP (FOR HIGH PRESSURE OF BANK 1 AND BANK 2)
(a) Replace the fuel pump (for high pressure of bank 1 and bank 2) Removal.
NEXT -- Continue to next step.

9. CHECK WHETHER DTC OUTPUT RECURS
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG) and turn the Techstream ON.
(c) Start the engine.
(d) Perform the driving test.
(e) Enter the following menus: Powertrain / Engine / Trouble Codes.
(f) Read DTCs.
Result:






B -- END
A -- REPLACE ECM