Last weekend was the first club DIY for me since last year. Both my M cars are up to date on maintenance items. That’s when I start to think about items that, as far as I know, are original to the car. Both cars are over 20 years old and preventative replacement can make sense.
I’m almost certain that my M3 ignition coils are original to the car, so I decided to replace them. Many do the spark plugs at the same time since the coils sit directly on the plugs. My spark plugs were replaced only about 12K miles ago when I had the Vanos system bullet-proofed. I also replaced the cabin air filter, since it had been 2.5 years, and I had to remove the receptacle it sits in to do the coils.
Here’s an excellent video from FCP Euro showing the replacement. There’s nothing like a detailed video for DIY confidence, especially when the job is shown on your exact BMW. There are several brands that make BMW ignition coils. After some research I went with Eldor coils. These were the coils used in the FCP video, but strangely were not listed as compatible for the E46 M3 on their site. As usual I saved a lot of money by not purchasing BMW-branded parts – the difference here was $33.32 each vs. $121.99! (And the rubber boots cost extra)!
Replacing M3 ignition coils is not a hard DIY. Once you have access you simply unplug each coil and pull it out. It sounds impressive to the uninitiated – “Yeah, I replaced my ignition coils” – but requires no mechanical knowledge or skill. It’s a perfect job to do yourself rather than paying $200+ for a BMW tech to do it for you.
A tip for the next guy – have a power wrench for removing the four T25 screws that secure the filter box. I had one, but not the Torx bits needed. That’s another benefit of a DIY – a friendly technician at Craftsman Reston lent me his.
I also took advantage of a lift to put two of my new wheels (sans tires) on the car to check fitment. More to come on that front soon. Suffice to say, the 9.5-inch width front wheels look a little tight. Enjoy the warmer weather and wash that pollen off your car.
