Fuel Injector: Service and Repair

Injector/pulse damper, replacement

Preparation




Drain the fuel injection system. See Fuel system pressure release Fuel System Pressure Release.
Remove the plastic hoses between the turbocharger (TC) / charge air cooler (CAC) and the air cleaner (ACL) / turbocharger (TC). Place them to one side and seal the openings. Applies only to B6xx4T.




Remove the upper section of the intake manifold. Cover the hole using tool 999 5723 Cap 999 5723 Cap. Only applies B6xx4S engines.
Remove the fuel rail.
Disconnect the connectors from the injectors.
Remove the mounting screws from the fuel rail.
Separate the fuel line's quick-release connector, see also: Fuel line, lock Service and Repair. Use tool 951 2666 Replaced by 9997298 951 2666 Wrench (Replaced by 9997298).
Spray universal oil or similar around the injector terminals on the intake manifold.





Gently work the fuel rail and injectors loose.

Note! Handle the injector valves carefully to avoid damaging the injector valves' nozzles with needles.

Removing injectors

Remove
- the screws holding the mounting rail to the fuel rail
- the mounting rail
- the injector.

Removing the pulsation damper

Remove
- the screws holding the mounting rail to the fuel rail
- the mounting rail
- the pulsation damper.

Installing injectors
Lubricate the O-ring for the new injector using petroleum jelly.
Install the injector.

Installing the pulsation damper
Lubricate the O-ring for the new pulsation damper using petroleum jelly.
Install the pulsation damper.

Finishing
Position the mounting rail. The injectors may need to be pulled away from the fuel rail a few millimeters to install the rail.
Tighten the mounting rail to the fuel rail.
Press down the fuel rail. Check that all injectors are correctly positioned.
Screw the fuel rail into place. Use new screws. Tighten to 10 Nm.
Install all connectors on the injectors.
Press the quick-release connector together until a clicking sound is heard. See Fuel line, lock Service and Repair.




Applies only to B6xx4T. Remove the seals. Install the plastic pipes between the turbocharger (TC) / charge air cooler (CAC) and the air cleaner (ACL) / turbocharger (TC).




Applies only to B6xx4S engines. Remove tool 999 5723. Clean the gasket faces and install a new gasket. Install the upper section of the intake manifold. Tighten to 17 Nm. Start from the center and tighten alternately.