| DTC Code | DTC Name |
|---|---|
| P0088 | Fuel Rail / System Pressure - Too High |
DESCRIPTION
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area | MIL | Memory |
|---|---|---|---|---|---|
| P0088 | Fuel Rail / System Pressure - Too High | The fuel pressure of the common rail exceeds 220000 kPa (2243.4 kgf/cm2, 31900 psi). (1 trip detection logic) |
|
Comes on | DTC stored |
| DTC No. | Data List |
|---|---|
| P0088 |
|
Tech Tips
For more information on the fuel supply pump (suction control valve) and common rail system, refer to System Description Click here.
When DTC P0088 is stored, check the internal fuel pressure of the common rail by entering the following menus: Powertrain / Engine / Data List / Fuel Press.
| Engine Speed | Fuel Press |
|---|---|
| Idling | Approximately 27000 to 45000 kPa |
| 3000 rpm (No engine load) | Approximately 45000 to 78000 kPa |
When there is an operating problem with the fuel supply pump (when Fuel Press is more than Target Common Rail Pressure due to a problem with the closing of the suction valve), the values of Injection Pressure Correction and Target Pump SCV Current decrease.
Check "Fuel Press", "Target Common Rail Pressure", "Target Pump SCV Current" and "Pressure Discharge Valve" in the freeze frame data.
MONITOR DESCRIPTION
The ECM stores this DTC if the fuel pressure inside the common rail is more than 220000 kPa (2243 kgf/cm2, 31900 psi). This DTC indicates that: 1) the suction control valve may be stuck open, or 2) there may be a short in the suction control valve circuit.
If this DTC is stored, the ECM enters fail-safe mode and limits the engine power. The fail-safe mode continues until the ignition switch is turned off.
CONFIRMATION DRIVING PATTERN
| DTC No. | DTC Detection Drive Pattern |
|---|---|
| P0088 | After idling for 60 seconds, repeat quick engine speed accelerations (from idling to 2500 rpm) for 30 seconds |
WIRING DIAGRAM
| *a | Suction Control Valve |
CAUTION / NOTICE / HINT
Note
After replacing the ECM, the new ECM needs registration (Click here ) and initialization Click here.
After replacing the fuel supply pump, the ECM needs initialization Click here.
Tech Tips
Read freeze frame data using the GTS. 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, and other data from the time the malfunction occurred.
PROCEDURE
CHECK ANY OTHER DTCS OUTPUT (IN ADDITION TO DTC P0088)
Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Enter the following menus: Powertrain / Engine / Trouble Codes.
Read Current DTCs.
| Result | |||
|---|---|---|---|
|
Tech Tips
If any DTCs other than P0088 are output, troubleshoot those DTCs first.
| DTC P0088 and other DTCs are output |
|
GO TO DTC CHART Click here |
| DTC P0088 is output |
|
CHECK FREEZE FRAME DATA (FUEL PRESS)
Connect the GTS to the DLC3.
Turn the ignition switch to ON and turn the GTS on.
Enter the following menus: Powertrain / Engine / Trouble Codes.
Record the stored DTC and freeze frame data.
| Result | ||||||
|---|---|---|---|---|---|---|
|
| B |
|
GO TO STEP 4 Click here |
| A |
|
CHECK HARNESS AND CONNECTOR
Tech Tips
If the MIL has illuminated before in the past, clear the DTC using the GTS before performing this inspection.
| *1 | Engine | *2 | Engine Wire |
| *3 | Common Rail Assembly (Fuel Pressure Sensor) |
*4 | Wire to Wire |
| *5 | ECM | - | - |
| *a | Vibration Method (Reference) | - | - |
| Result | |||
|---|---|---|---|
|
| MIL comes on |
|
REPAIR OR REPLACE HARNESS OR CONNECTOR Click here |
| MIL does not come on |
|
REPLACE SUCTION CONTROL VALVE
Replace the suction control valve.
Tech Tips
Before replacing the supply pump assembly, check that the wire harness between the suction control valve and ECM is not shorted to ground.
When there is a malfunction in the wire harness, Target Pump SCV Current is outside the range of 923 to 1123 mA when idling, and outside the range of 1013 to 1212 mA when the engine is running at 2500 rpm without load.
If there are no problems with the engine condition during idling, it is not necessary to perform the above wire harness inspection.
When the wire harness between the suction control valve and ECM is not shorted to ground, it can be assumed that DTC P0088 was stored due to a malfunction in the operation of the suction control valve. Therefore, it is necessary to replace the supply pump assembly.
| Result | ||
|---|---|---|
|
| NEXT |
|
BLEED AIR FROM FUEL SYSTEM
Bleed the air from the fuel system.
| Result | ||
|---|---|---|
|
| NEXT |
|
PERFORM SUPPLY PUMP INITIALIZATION
Perform supply pump initialization.
| Result | ||
|---|---|---|
|
| NEXT |
|
CHECK DTC OUTPUT
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Clear the DTCs.
Turn the ignition switch off and wait for 30 seconds or more.
Start the engine and turn the GTS on.
After idling for 60 seconds, repeat quick engine speed accelerations (from idling to 2500 rpm) for 30 seconds.
Confirm that the DTC is not output again.
Tech Tips
Perform the following procedure using the GTS to determine whether or not the DTC judgment has been carried out.
Enter the following menus: Powertrain / Engine / Utility / All Readiness.
| Tester Display |
|---|
| All Readiness |
Input DTC P0088.
Check the DTC judgment result.
| Result | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
Tech Tips
If STATUS is INCOMPLETE or N/A, race the engine to 2500 rpm repeatedly for 30 seconds and increase the idling time.
| B |
|
END |
| A |
|
REPLACE ECM
Replace the ECM.
| Result | ||
|---|---|---|
|
| NEXT |
|
GO TO STEP 13 Click here |
REPAIR OR REPLACE HARNESS OR CONNECTOR
Repair or replace the harness or connector.
| Result | ||
|---|---|---|
|
| NEXT |
|
CHECK HARNESS AND CONNECTOR
Tech Tips
If the MIL has illuminated before in the past, clear the DTC using the GTS before performing this inspection.
| *1 | Engine | *2 | Engine Wire |
| *3 | Common Rail Assembly (Fuel Pressure Sensor) |
*4 | Wire to Wire |
| *5 | ECM | - | - |
| *a | Vibration Method (Reference) | - | - |
| Result | |||
|---|---|---|---|
|
| MIL does not come on |
|
GO TO STEP 13 Click here |
| MIL comes on |
|
REPLACE COMMON RAIL ASSEMBLY
Replace the common rail assembly.
| Result | ||
|---|---|---|
|
| NEXT |
|
BLEED AIR FROM FUEL SYSTEM
Bleed the air from the fuel system.
| Result | ||
|---|---|---|
|
| NEXT |
|
CONFIRM WHETHER MALFUNCTION HAS BEEN SUCCESSFULLY REPAIRED
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Clear the DTCs.
Turn the ignition switch off and wait for 30 seconds or more.
Start the engine and turn the GTS on.
After idling for 60 seconds, repeat quick engine speed accelerations (from idling to 2500 rpm) for 30 seconds.
Confirm that the DTC is not output again.
Tech Tips
Perform the following procedure using the GTS to determine whether or not the DTC judgment has been carried out.
Enter the following menus: Powertrain / Engine / Utility / All Readiness.
| Tester Display |
|---|
| All Readiness |
Input DTC P0088.
Check that STATUS is NORMAL.
Tech Tips
If STATUS is INCOMPLETE or N/A, race the engine to 2500 rpm repeatedly for 30 seconds and increase the idling time.
| Result | ||
|---|---|---|
|
| NEXT |
|
END |