There are several different parts that make up the ignition system of your Mini Cooper Countryman, and all of them are important for your engine to be able to function properly. Spark plugs are something you should be checking on a regular basis, as the health of your engine is tied so closely with their efficiency and performance. Spark plugs light the fuel and air mixture needed to get your engine started. If your spark plugs start to fail, you'll most noticeably have issues when trying to get your car going. You could experience cold starts or misfiring of the engine. You could find that the engine is cranking several times before it finally gets going. You could also have reduced fuel efficiency. These can all be signs that you may need to have your spark plugs changed. Carbon build up can cause them to go bad over time, as well as general wear and tear that occurs to all parts. It's important that when you're replacing your spark plugs, you are doing so with high quality OEM components that are made for your specific make and model. Only OEM spark plugs will be made according to the measurements that your Countryman has so they will install properly. Find the set of genuine spark plugs your car needs here at Mini of Kennesaw.