The ignition lock in your Porsche 928 is made up of the ignition switch and the lock cylinder. Both of these components can be found within the steering column. A damaged ignition lock will prevent you from being able to turn your vehicle on or off. If either of these components become damaged you should replace them as soon as possible. You can pick up the tools and components needed from your local auto store.
Open up the bonnet of your Porsche and locate the battery. Remove the clamp bolt attached to the negative terminal by loosening it with a wrench. Lift the negative cable away from the terminal.
Enter the drivers seat of your vehicle. Pry the steering wheel cover away from the wheel by removing the connectors located around the edge of the wheel.
Lift up the air bag and horn out of the steering wheel. Follow their wiring until you reach their connectors. Remove the connectors and completely remove them both from the steering wheel. Take care not to damage the air bag as you will need to completely replace it if any damage at all occurs.
Use a Phillips-head screwdriver to remove the screws attached to the steering column sleeve. Slide the sleeve away from the column. Use a wrench to remove the mounting bolts attached to the ignition switch.
Place your key in to the ignition. Turn it to the locked position to expose the retaining pin. Unhook the retaining pin and lift the ignition switch and lock cylinder from the steering column.
Attach the new ignition switch to the new lock cylinder by connecting them with the locking tab. Reattach the lock cylinder and ignition switch to the steering column by fixing them in place with the mounting bolts. Reattach the steering column and steering wheel by following the removal steps in reverse.