Ignition Coil Replacement – BMW B46 Turbo 4-Cylinder Engine
Step 1 - Purchase Parts
Ignition Coil
We have long ago established here at the Repair Guide that when it comes to engine electronics, the best practice is to stay away from aftermarket parts. The same holds true with coils. Some manufacturers may claim they are "OEM", but in the end the only way you know you are getting factory quality is to install Genuine BMW. These are the same factory ignition coils that would be installed at the dealership.
Step 2 - Repair Procedure
- Remove the top fasteners (1).
- Unlock the latching mechanism (3).
- Remove the cover (2).
- Remove the top fasteners (1).
- Unlock the latching mechanism (3).
- Remove the cover (2).
In the next step the front strut brace is removed. The front strut brace is an integral part of the vehicle's suspension and must be reinstalled correctly.
Unsnap the top cover. Remove the two anchor bolts (1).
Remove the two bolts anchoring the strut to the body of the vehicle (2).
Remove the strut brace.
- Detach the positive battery cable from the sealing gasket (2).
- Remove the anchor rivet (1).
- Remove the sealing gasket in the direction shown in image (2).
Be careful when removing the acoustic engine cover. They are prone to breaking when excessive force is applied. Try and pull the cover loose close to the mounting points, not along the edges.
- Pull the acoustic engine cover loose from the mounting points as shown in the image and remove from the vehicle.
- Unlock and remove the electrical connector (1).
- Remove mounting bolt (2).
- Grasp the ignition coil and remove it from the engine (3).
- Repeat for other three coils.
Part Needed - 4 x ignition coil 12138643360
- Install a new ignition coil 12138643360 in the engine.
- Install the mounting bolt (2) and torque to 8Nm (6 ft-lb).
- Reconnect the electrical plug (1).
If you are having issues reinstalling the acoustical engine cover, try coating the rubber mounts with a thin layer of liquid detergent like Dawn. This will help the cover slip easily back onto its mounts.
- Reinstall the parts following steps 1-5 above in reverse.
- Strut brace mounting bolts torque to 56Nm (41 ft-lb).