Contents: Removal ⇓ Installation ⇓
Faulty injectors can cause severe engine knocking and damage to its bearings. If such signs appear, you need to switch the engine to idle mode and loosen the union nuts of the high-pressure fuel lines one by one. If the knocking disappears after unscrewing one of the union nuts, this indicates a malfunction of the corresponding injector.
Faulty injectors can also be detected by loosening the union nuts of the high-pressure fuel lines one by one while the engine is running at high idle speed. If the engine speed remains constant after loosening the union nut, the corresponding injector is faulty. It can be checked with a pressure gauge in a workshop. The injection pressure value is 134±4bar.
The first signs of damage to the injectors are the following:
- misfires (flashes) in cylinders;
- knocking in one or more cylinders;
- engine overheating;
- engine power reduction;
- heavy black smoke from the exhaust pipe;
- high fuel consumption.
Removal
Disconnect the negative cable from the battery.
Note: This will erase the data from the electronic memory blocks. See instructions "Electrical equipment".
Thoroughly clean the high-pressure fuel lines and return fuel lines with a special agent or clean diesel fuel. If the high-pressure fuel line fastening brackets are removed, mark their installation position.
Completely remove the high-pressure fuel lines by unscrewing the union nuts with a special open-end wrench.
Caution: Do not change the shape of the fuel lines. Put suitable protective caps on the injectors and on the fuel injection pump to prevent dirt from getting inside.
Carefully pull the return fuel lines (3) off the injectors. These fuel lines connect the injectors to each other. The last injector, i.e. the one closest to the gearbox, has a blind cap.
Unscrew the injectors using a 27 mm deep socket. Protect the injectors at the bottom from dirt using protective caps.
Caution: Care must be taken to ensure that the nozzles do not fall out.
Remove the heat shield (1).
Installation
It is essential to use heat shields between the cylinder head and the injectors. The recess should be facing upwards, the arrow should point towards the cylinder head.
Tighten the injectors to 75 Nm.
Tighten the union nuts of the high-pressure fuel lines to a torque of 20 Nm.
If they were removed, insert the mounting brackets in accordance with the previously made markings.
Install the return fuel lines.
Connect the negative cable to the battery. Set the clock and enter the required codes.
Start the engine and check the fuel system for tightness.