BMW N54 Spark Plug Replacement
How Often You Should Change Your Plugs & Why
For the N54 engine the spark plugs should be changed every ~40,000 miles. Tuned N54’s should have their plugs changed every ~20,000 miles as the additional power will put a higher demand on the spark plugs. The more horsepower and boost you are running will require shorter intervals for changing spark plugs. It is recommended you change the spark plugs and ignition coils before tuning your N54 as weak coils and plugs may cause misfires.
Get your spark plugs here: N54 Spark Plugs
Spark plug thin-walled socket: 14mm 12-Point Socket
- 1)Wrench w/ extension
- 2)8mm Socket
- 3)5mm Allen Wrench
- 4)14mm, 12-Point THIN WALLED Socket
1)Remove the cabin air filters and all of the housing around it. There are 2 wires that need to be removed before pulling off the housing.
a.Your engine should now look like this:
2)Remove the engine cover. There are 4 5mm bolts that hold it down – 1 in each corner. The bolt in the back left is hard to reach so I recommend placing a magnet just below the bolt in-case you drop it.
3)With the cover removed you will see your coil packs. Lift the tab and it will pop the wires out.
4)Move the wires to the side and lift the tab to ~90 degrees. Gently pull up on the coil pack and it will come out.
a.If you’ve never removed your coil packs before it may require quite a bit of force – just make sure you gently apply more & more force until it starts sliding up.
5)With the coil packs removed you will have access to the spark plugs. Removing the plugs requires the use of a special thin-walled 14mm 12 point socket. I tried using a normal 14mm craftsman socket and it was too fat to grip the spark plug.
6)Remove the old plugs and replace them. The new spark plugs should be tightened to 17 ft-lbs of torque.