INSPECT FOR FUEL LEAK
CAUTION:
During Active Test mode, the engine speed becomes high and the combustion noise becomes loud, so pay attention.
During Active Test mode, the fuel pressure becomes high. Be extremely careful not to expose your eyes, hands, or body to escaping fuel.
Check that there are no leaks from any part of the fuel system when the engine is stopped. If there is fuel leakage, repair or replace parts as necessary.
Start the engine and check that there are no leaks from any part of the fuel system. If there is fuel leakage, repair or replace parts as necessary.
Disconnect the return hose from the common rail.
Start the engine and check for fuel leaks from the return pipe.
If there is fuel leakage, replace the common rail.
Connect the intelligent tester to the DLC3.
Start the engine and turn the intelligent tester main switch on.
Select the Fuel Leak test from the Active Test mode on the intelligent tester.
If the intelligent tester is not available, fully depress the accelerator pedal quickly. Increase the engine speed to the maximum and maintain that speed for 2 seconds. Repeat this operation several times.
Check that there are no leaks from any part of the fuel system.
Note
A return pipe leakage of less than 10 cc (0.6 cu in.) per minute is acceptable.
If there is fuel leakage, repair or replace parts as necessary.
Reconnect the return hose to the common rail.
CHECK PRESSURE DISCHARGE VALVE
Tech Tips
This is the procedure for troubleshooting fuel pressure control malfunctions and combustion problems.
Malfunctions can be determined by checking the fuel pressure when performing fuel cut and operating the pressure discharge valve with the intelligent tester.
During "Pressure Discharge Valve Check", the intelligent tester measures the fuel pressure while the engine is running, after the engine is stopped, and after the pressure discharge valve operates.
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON.
Turn the intelligent tester on.
Note
The following conditions must be met:
The engine is idling.
The vehicle is stopped.
The fuel pressure is not extremely high (below 100000 kPa).
The fuel pressure is not extremely low (higher than 26000 kPa).
The fuel pressure sensor is normal.
The battery voltage is higher than 8 V.
Tech Tips
When the common rail pressure is unstable, the fuel pressure may decrease to a level where the test cannot be performed. In this situation, wait until the common rail pressure meets the test condition, and then perform the test.
Enter the following menus: Powertrain / Engine / Utility / Pressure Discharge Valve Check.
Press "Next".
Press "Next" again to proceed.
Select "Close to Open Check".
Press "Next".
Read the value of "Open and Engine OFF".
| OK |
|---|
| 0.5 MPa or less |
Tech Tips
When the system is normal, the value of "Open and Engine OFF" should be at or close to 0 MPa.
When the fuel pressure value of "Open and Engine OFF" does not become equal to or less than 0.5 MPa, the pressure discharge valve may be stuck closed.
When the fuel pressure values of "Close and Engine OFF" and "Open and Engine OFF" are both 0 MPa, the pressure discharge valve may be stuck open or there may be a fuel leak.
Perform "Always Closed Check" if the value is not 0 MPa when the pressure discharge valve is open during "Close to Open Check". If the results are the same as during "Close to Open Check", there is a pressure discharge valve operation malfunction.
| *1 | Fuel Press (Always Closed Check) | *2 | Fuel Press (Close to Open Check) |
| *3 | Engine Speed | *4 | Fuel Cut Operation Signal |
| *5 | Pressure Discharge Valve Operation Prohibition | *6 | Pressure Discharge Valve Operation (Always Closed Check) |
| *7 | Pressure Discharge Valve Operation (Close to Open Check) | - | - |
| *a | Fuel Press Recorded Point | *b | Closed (on) |
| *c | Open (on) | - | - |
|
Pressure Discharge Valve Operation Start | - | - |
BLEED AIR FROM FUEL SYSTEM
Using the hand pump mounted on the fuel filter cap, bleed the air from the fuel system. Continue pumping until the pump resistance increases.
Note
Hand pump pumping speed: Max. 2 strokes/ sec.
The hand pump must be pushed with a full stroke during pumping.
When the fuel pressure at the supply pump inlet port reaches a saturated pressure, the hand pump resistance increases.
If pumping is interrupted during the air bleeding process, fuel in the fuel line may return to the fuel tank. Continue pumping until the hand pump resistance increases.
If the hand pump resistance does not increase despite consecutively pumping 200 times or more, there may be a fuel leak between the fuel tank and fuel filter, the hand pump may be malfunctioning, or the vehicle may have run out of fuel.
If air bleeding using the hand pump is incomplete, the common rail pressure does not rise to the pressure range necessary for normal use, and the engine cannot be started.
Check if the engine starts.
Note
Even if air bleeding using the hand pump has been completed, the starter may need to be cranked for 10 seconds or more to start the engine.
Do not crank the engine continuously for more than 20 seconds. The battery may be discharged.
Use a fully-charged battery.
When the engine can be started, proceed to the next step.
If the engine cannot be started, bleed the air again using the hand pump until the hand pump resistance increases (refer to the procedures above). Then start the engine.
Turn the ignition switch off.
Connect the intelligent tester to the DLC3.
Turn the ignition switch to ON and turn the intelligent tester on.
Clear the DTCs Click here.
Start the engine.*1
Enter the following menus: Powertrain / Engine / Active Test / Test the Fuel Leak.*2
Perform the following test 5 times with on/off intervals of 10 seconds: Active Test / Test the Fuel Leak.*3
Allow the engine to idle for 3 minutes or more after performing the Active Test for the fifth time.
Tech Tips
When the Active Test "Test the Fuel Leak" is used to change the pump control mode, the actual fuel pressure inside the common rail drops below the target fuel pressure when the Active Test is off, but this is normal and does not indicate a pump malfunction.
Enter the following menus: Powertrain / Engine / DTC.
Read Current DTCs.
Clear the DTCs Click here.
Tech Tips
It is necessary to clear the DTCs, as DTC P1604 or P1605 may be stored when air is bled from the fuel system after replacing or repairing fuel system parts.
Repeat steps *1 to *3.
Enter the following menus: Powertrain / Engine / DTC.
Read Current DTCs.
| OK |
|---|
| No DTCs are output. |