When I recently put my 2010 Mini Cooper S into the shop for a new windshield, I was notified that my car was due for spark plugs. Through a bit of research, I found out that it’s a pretty easy DIY job, so that’s what I chose to do. Sounds simple, but was it really? Read on to find out.
The R56-generation Mini Cooper S, which was produced for the 2007 to 2014 model years (2006 to 2013 calendar years), is where my 2010 falls, so this DIY will work for anyone with those model year, turbocharged cars. Apparently, the spark plugs on the Cooper S model are only good for 30,000 miles, whereas for the regular Cooper, they’re good for 100,000.
I compared the prices of my local dealer, where the Mini usually goes for service, and an independent shop, which came highly regarded. Both were high enough that I looked online to check the difficulty of doing it myself. What I found was that it looked easy, so long as you had the right tools. Even having to buy a few hand tools, I realized that I’d save a fair chunk of change by doing this job myself, so I set out to get all the pieces together.
Let’s review what you’ll need to complete this job: (Amazon Affiliate Links)
- Four (4) spark plugs. There are a ton of options, but I went with locally-sourced Denso Iridium spark plugs. They seem to work well. The model number for these plugs is SXU22HCR11S.
- 3/8″ drive Ratchet
- 3/8″ 6″ Extension Bar
- 3/8″ 14mm 12-point Deep Socket
- 3/8″ 5/8″ 6-point Deep Socket
- Magnetic Pick-Up tool
- Anti-seize paste (I used a $1.49 pack of anti-seize I found at the local parts store’s checkout counter)
None of the online research I did showed that the magnetic pick-up tool was required, but I found it easier than using a set of needle-nose pliers to remove and drop in the plugs.
The difficulty of this job is easy-to-medium. As long as you’re comfortable using hand tools, you’ll be fine.
Let’s get started!
Step 1: Get to the old spark plugs
Start by lifting the retaining clips on top of each spark plug. Then, gently pull the spark plug wire out of the coil pack. This frees up the coil pack and plug boot. Lift on the rubber tab on each spark plug boot, and pull up. You’ll hear a pop, and the boot will be free. Set them aside. I hear that the coil packs and plug boots are interchangeable, but I kept them lined up on a work bench to keep them in order.
Step 2: Remove the old spark plugs
Using the 14mm 12-point deep socket, loosen each spark plug. This takes a while, since these spark plugs have an unusually long set of threads. Once they are loose, remove them with the magnetic pick-up tool. If you don’t have one, needle-nose pliers will suffice, but really, the pick-up tool made the job a lot easier, as you’ll see in the next step. Note that these are BMW-style plugs, which are 12-point instead of the normal 6-point ones found in other makes.
Step 3: Install the new spark plugs
After removing the old plugs, I put a small amount of paste on the threads of the new plugs. Simply wipe a very little bit on the plugs in a straight line, as the paste will be spread into the rest of the threads when you install the plugs.
Next, to install the plug, I first tried to use a regular 5/8″ spark plug socket, since the new plugs are 6-point, unlike the 12-point OEM plugs. Your mileage may vary, but at this point, it’s a moot point, since you’ve got the right tools already. This didn’t work for me, since my socket was physically too wide to fit into the hole in the engine cover. I ended up using my pick-up tool to start each plug, and then a 5/8″ 6-point deep socket to tighten them down. Make sure you don’t over-tighten the plugs, as they will break, which is definitely not good. My research showed a need for 18.5 foot-pounds of torque on each plug, but I simply tightened them until snug and then added a quarter turn for good measure. The plugs are holding just fine, so no need for a torque wrench.
Step 4: Reconnect the wiring
Now that the new plugs are installed, put each boot/coil back onto their respective spark plugs and push down until the rubber seals are seated. Then, connect each spark plug wire and push down on the retaining clip until it clicks into place.
You’re all done! Even if you need to buy a few tools, you’ve still saved yourself a good $100 or more, given dealer prices to do the job.
by John Suit