Fuel Rail: Service and Repair
OVERHAUL
IMPORTANT POINTS - REMOVING
1. CLEAN OFF SURROUNDING AREA OF THE NOZZLE AND THE FUEL LINE CONNECTORS.
NOTICE: If foreign matter is allowed to enter the combustion chamber, engine trouble may result.
2. REMOVE THE FUEL INJECTION PIPE.
1. Remove the return pipe.
2. Loosen the injection pipe nut.
3. Remove the force feed pipe.
NOTICE: Cover open ends of the pipes and fuel supply pump to prevent entry of dirt.
3. REMOVE THE COMMON RAIL
1. Disconnect the connectors.
2. Remove the 2 bolts and common rail.
IMPORTANT POINTS - DISASSEMBLY
1. REMOVE THE FLOW DAMPER
1. Using a 19 mm (0.748 in) width across flats deep socket wrench, loosen the flow damper by turning in counter- clockwise direction.
2. Remove the flow damper assembly (spring, piston and stopper).
NOTICE: Be careful not to drop parts into common rail.
2. REMOVE THE PRESSURE LIMITER.
1. Using a 19 mm (0.748 in) width across flats deep socket wrench, loosen the pressure limiter by turning in counter- clockwise direction.
2. Remove the pressure limiter.
3. Using tweezers, remove the gasket.
NOTICE: Be careful not to damage the seal surface.
3. REMOVE THE COMMON-RAIL PRESSURE SENSOR.
1. Using a 30 mm (1.181 in) width across flats deep socket wrench, loosen the common -rail sensor by turning in counter- clockwise direction.
2. Remove the common-rail sensor.
NOTICE:
- Never reuse a used common-rail pressure sensor.
- Because if it is reused, its thread may break.
IMPORTANT POINT - ON - VEHICLE INSPECTION
1. INSPECT THE PRESSURE SENSOR.
1. If the diagnosis monitor lamp come on, and the following malfunction is displayed at the diagnosis system, replace the pressure sensor.
a. Harness disconnection or short-circuit in the pressure sensor circuit
b. Common rail pressure does not change at a certain time while the engine is running.
2. Measure the resistance between terminals.
If not standard value, replace sensor.
Standard: (Engine stop condition)
Terminal 2 and 3 6.5 - 18.5 kohms
Terminal 1 and 2 0.5 - 3.0 kohms
2. INSPECT THE PRESSURE LIMITER.
1. Remove the follow screw from pressure limiter.
2. Block pipe ends to prevent fuel leak.
3. Install the union to the pressure limiter.
4. Set a vinyl hose to the union and set a drain tank.
5. Start the engine. If the fuel flows continuously, replace the pressure limiter.
WARNING: When the pressure limiter is working, fuel flows out at a high temperature and pressure. Serious injury like scalding could result from this hot fuel being blown out under pressure.
3. INSPECT THE FLOW DAMPER.
1. Check that the piston is not sticking in the body. If the piston sticks, replace the flow damper.
2. Inspect the contact surface 1 between piston and fuel supply port. If there is wear and damage, replace the flow damper assembly.
3. Inspect clogging on the piston orifice. Clean or replace the flow damper assembly.
IMPORTANT POINTS - ASSEMBLY
NOTICE:
- Every part of the common rail should be washed clean carefully laying threaded side below.
- Be careful to prevent dust from entering inside.
1. INSTALL THE COMMON-RAIL PRESSURE SENSOR.
1. Install the new common-rail pressure sensor.
NOTICE:
- Apply clean grease to the pressure sensor as shown in the figure.
- Be careful to prevent dust from entering inside.
2. Tighten the new pressure sensor.
Tightening Torque: 98 N.m {10.0 kgf.m, 72 ft.lbf}
2. INSTALL THE PRESSURE LIMITER.
1. Install the pressure limiter with a new gasket.
Tightening Torque: 172 N.m {17.5 kgf.m, 126 ft.lbf}
3. INSTALL THE FLOW DAMPER.
1. Install the stopper.
2. Install the flow damper with the piston and spring.
Tightening Torque: 128 N.m {13.05 kgf.m, 94 ft.lbf}
IMPORTANT POINT - INSTALLATION
1. INSTALL THE COMMON RAIL ASSY.
1. Install the common rail with 2 bolts.
Tightening Torque: 28.5 N.m {2.9 kgf.m, 21 ft.lbf}
2. Connect the connector.
NOTICE:
- Be careful to prevent dust from entering inside the common rail and parts when the mounting is performed. Dust and foreign matter must not adhere to the seats of the parts and common rail main unit.
- After the operation is completed, wipe off the fuel which leaked and start the engine. Make sure that the fuel does not leak again.
3. Tighten the injector pipe nuts to the specified torque.
Tightening Torque: 44 N.m {4.5 kgf.m, 32 ft.lbf}
4. Tighten the force feed pipe nuts to the specified torque.
Tightening Torque: 44 N.m {4.5 kgf.m, 32 ft.lbf}
NOTICE:
- If the tightening torque of the nuts is less than the specified value, it may cause a fuel leak. If the tightening torque of the nuts is greater than the specified value it may have a negative influence on the engine function. As a result, always perform torque management.
- After mounting is completed, fuel leak check using "check functions" menu of PC DIAGNOSTIC SOFTWARE.