Upgrade in every way from the previous mode, D1 SPEC auto timer II can automatically determine the necessary amount of after idling time. A manual mode allows the user to preset desired idling times from 0 sec. to 10 minutes in 16 increments. By inputting O2 sensor voltage, D1 SPEC auto timer II can also display theoretical air fuel ratio. Since the auto timer II uses the factory O2 sensor which is primarily designed for emissions, the readings may not be as accurate as racing air fuel ratio monitors. Besides, the timer can also display other critical data- voltage and battery situation. To prevent theft, the handbrake safety feature shuts off the vehicle when the handbrake is released without the ignition key.