Mini Cooper 2007-2013: How to Replace Ignition Coils and Spark Plugs
The dealer or a pro will charge you a good deal to do this task that can easily be done in your own garage with a minimum of tools.
This article applies to the Mini Cooper (2007-2013).
Your Mini's ignition system is pretty simple to understand; it uses ignition coils seated atop the spark plugs to deliver electricity to the plugs and make them fire. When either a plug or coil goes bad, your Mini will develop a misfire. Consider replacing the plugs every 50,000 miles and your coils every 100,000 miles for trouble-free performance. If either of those intervals are close approaching, it's time to gather supplies. Four spark plugs will set you back about $20 to $40, and coils will cost about $150 to $200 for all four. This job should only take you about an hour with no special tools needed and no strong mechanical aptitude. If you are determined to get this job done yourself, read on to learn what needs to be done and keep a lot of those greenbacks in your wallet.
Materials Needed
- Ratchet and deep well socket or spark plug socket (14mm) and at least a six inch extension
- Replacement plugs (4-pronged type seem to be the best)
- Replacement coils (if needed)
Step 1 – Pop the hood and locate coils
Lift your hood and locate the spark plugs as well as coils on the top front of the engine block. You will need a 14mm deep well plug socket because of the German style of plugs used in these cars. As there are only four cylinders in your engine, you will only have four plugs and four coils.
Step 2 – Pop off the coil boots and remove the coils
It's a multi-step, yet easy process to get the coils out:
- Flip up the covers. They pivot on the side away from you.
- Pull the electrical connection out from each coil after the cover is flipped up.
- Once the electrical connection is removed, pull up on the rubber tab and grab the top of the coil boot.
- Pull up on the tab and the top of the boot and the coil will pull right out. This may take a little effort to get it out.
- Set the coil aside (for re-use) or remove it completely from the boot for replacement if you purchased new coils as well.
Figure 2. Flip the boot covers up and disconnect the electrical harnesses from each coil. 
Figure 3. Locate the rubber tab and get a grip. 
Figure 4. Grab the top of the boot, hold the rubber tab and pull straight up. 
Figure 5. The coil is removed.
Step 3 – Remove your spark plugs
Once you have the coil packs out, you only need to remove the plugs.
- Attach your deep well 14mm socket to your ratchet and put it down in the hole that was opened up when you removed the coils.
- Unless you have a special socket for these German engineered plugs (if they are OEM), they may not come out inside your socket.
- If the plug came out with your socket, you are almost there. If not, you will need to pull them out from the engine core. A length of rubber hose, such as the kind used for fish aquariums, work well.
- Insert the tube into the hole and push it onto the stem of the spark plug and it should pull right out.
- You can do all four at once, or one at a time.
- Now is a good time to check the condition of your plugs, which will tell a tale of how your engine is running.
- A three or four pronged plug normally does not need gapped; any others should be gapped around .26 or .27.
- Carefully place the new plug into the hole, or insert it into your socket if it stays put. (You can use your tubing or a long nosed, needle nose plier to do this.)
- Tighten the spark plug to the required spec, which is usually about a 3/4 turn beyond snug. Be careful that you do not over-tighten them.
Figure 6. Insert your ratchet with extension and 14mm socket into the hole and loosen the spark plug. 
Figure 7. Insert the plug into the bunghole. You can use your special socket tool, a length of tubing or long needle nose pliers to do this. 
Figure 8. Initially hand-tighten your plugs only to avoid cross-threading. Once tight, snug it with your ratchet only about a 3/4 turn. 
Figure 9. Be sure to check the condition of your old plugs to make sure your engine is running optimally.
Pro Tip
Some owners prefer to use some anti-seize compound on the threads, while others will say to avoid using it at all. Use your discretion, but if you do not over-tighten your plugs, it should not be an issue.
Step 4 – Replace your coils and fire up your Mini
If you are replacing your coils, swap them out now and then replace them into your engine. They don't need to be in any special order. Slide the coils back into the bung hole. Make sure the rubber tab fits in between the slots, as they were when you started. Push them all the way down into place and make sure they are snug. Push the electrical connectors back in and the cap will partially engage. Press the cap back down until it clicks. Repeat for each cylinder and you are done. Start up your Mini and make sure she fires right up and sounds smooth. If it sounds rough, it is likely that a coil just isn't seated the right way. Double check. If they are all good, then you may need to pull a plug one at a time, checking the gap and firing her back up between each gap check to be sure to isolate the one that needs correcting. If all is well, take her for a test ride and be very happy that you didn't pay someone to do this simple task for you.
Featured Video: Replacing Spark Plugs on 2007 Mini Cooper S
Related Discussions
- R56 Spark Plug Gap - NorthAmericanMotoring.com
- Are My Spark Plugs Good? - NorthAmericanMotoring.com
- Coil Removal to Get to Spark Plugs - NorthAmericanMotoring.com
- 2008 R56 Spark Plug Install - NorthAmericanMotoring.com
- Spark Plugs, Eh? - NorthAmericanMotoring.com
