Genuine 2009 BMW 335i Fuel Injector

2009 BMW 335i Fuel Injector Parts Questions & Experts Answers

• Q:

  What are the steps and precautions for replacing fuel injectors in the N54 six cylinder engine on 2009 BMW 335i?

  Posted by Mitzi A.

  A:

  Remember to replace the uncoupling element and the PTFE sealing ring, and remove the PTFE protective cap no more than 10 minutes before installation, as the sealing ring swells once the cap is removed. If injector adaptation is necessary, note the injector tolerance range numbers for each corresponding cylinder. When working at the cylinder head, install the injector and the hold-down bracket, ensuring the fastener is finger tight to allow for injector adjustment, then install the electrical connector. Verify that the hold-down bracket is correctly installed, and remove and discard the copper seals on the high-pressure lines that were installed at the factory. Connect the high-pressure line finger tight, and if reusing the line, coat the nut threads with gear oil. Remember that the high-pressure line may only be retightened 10 times. If both nuts on the line cannot be easily installed by hand, adjust the injector's position as needed. If the fuel lines cannot be easily installed by hand, rotate the injector in the direction of the arrows until the high-pressure line nuts can be tightened by hand. Tighten the fastener for the hold-down bracket using the specified tightening sequence, first tightening the nut with the BMW special tool while holding the injector with a wrench, then tightening the nut with the special tool. Clean all fuel from the ignition coil hole, check the fuel system for leaks, perform injector adaptation, and check for fault codes while resetting the ECM memory.

  Answered by BMW Parts Specialist Blaine / Mar 07, 2026