1. Locate the odometer reset knob, which is usually located on the dashboard.
2. Insert the key into the ignition and turn it to the "On" position.
3. Press and hold the odometer reset knob until the odometer resets to zero.
4. Release the odometer reset knob and turn the key to the "Off" position.
Please note that this process may vary depending on the exact model of your 1988 Porsche. If you are unable to find the odometer reset knob or reset the odometer, you may need to consult your vehicle's owner's manual or contact a Porsche dealership for assistance.
