DIY E46 Ignition Coil Replacement

The BMW E46 has a coil over plug ignition setup; there are no spark plug wires and every spark plug has its own ignition coil. From time to time, these coils will fail causing a misfire to its respective cylinder and often triggering a check engine light. The ignition coils are located right above the spark plugs and mount on the top of the engine right under the micro fiber housing.

Instructions

1

Lift the vehicle hood and support it with the hood prop rod.

2

Visually locate the micro filter housing cover and remove it by gently pulling up on it by hand. Remove the cabin micro filter by lifting it directly up and out of the micro filter housing.

3

Remove the four Torx screws securing the micro filter housing to the top of the engine with the ratchet and proper size Torx bit. Lift the micro filter housing away from the engine to expose the ignition coils.

4

Remove the two mounting nuts that hold the ignition coil in place. Gently pull up on the silver tab and pull the wire pigtail away from the coil plug. Gently lift the coil strait up and away from the engine.

5

Gently push the new coil into the coil boot bore until the ignition coil rests in its mounting position. Thread on the two coil mounting nuts and tighten them with the socket and ratchet. Plug the pigtail into the ignition coil plug and clip the silver bar into place.

6

Set the micro filter housing back into its position. Install the Torx screws and tighten them with the Torx bit set. Place the cabin microfilter into the filter housing. Close the microfilter housing cover.

7

Lift the hood off of the prop rod and secure the prop rod into its respective holder. Lower the hood and drop it to ensure it latches properly.