How to Change a BMW Z3 Flat Tire

1. Remove the tool kit under the trunk floor. Pull up the strap on the trunk floor to lift the panel, and remove the tool kit. The kit contains all the necessary tools.
2. Slide the centering pin through the aperture near the top of the spark plug wrench. You'll use this tool to loosen the spare tire at one of its mounting points.
3. Open the plastic storage bin toward the right side of your trunk. Unscrew the plastic nut at the bottom of the bin with your fingers, revealing a metal hex nut. Use the spark plug wrench to remove the metal nut.
4. Use the combined pull cord and socket wrench to release the spare tire. Thread the socket over the hex nut that protrudes from the tool kit, and unscrew it with the handle. Hold tightly to the handle. Pull on the handle so the spare wheel tray lifts slightly. At the same time, squeeze together the metal clip near the hex nut you just loosened. This will release the spare tire and its cradle, putting the weight on the handle. Slowly lower the tire and cradle to the ground beneath your Z3.
5. Push the tire wedge from the tool kit under the rear of the front tire opposite the side that you'll be lifting.
6. Pull the tire and cradle out from under the car. The tire will still be in a bin when you remove the tire from the cradle; it's connected to the bin via a pressure hose on one side. Lift it from the other side and flip it out of the bin. Quickly loosen the nut connecting the pressure hose to the tire. There should only be a quick spurt of air.
7. Remove the jack from the trunk and line it up with the jack points just in front of the rear wheel or just behind the front wheel. Loosen the lug nuts a quarter turn each with the lug wrench, then jack the car up until the flat tire is off the ground. Loosen the lug nuts in a star pattern, first loosening one nut and then the nut directly across from it.
8. Finish loosening the nuts and remove the wheel. Replace it with the spare, and tighten the lug nuts. Put all tools back in their compartments. Stow away the flattened tire until you can fix or dispose of it. You can stash the tire in the white sack from the tool kit.