A system for automatically adjusting the temperature and carbon monoxide level in an occupied passenger compartment of a vehicle includes sensors for sensing carbon monoxide levels, temperature, and occupants in the passenger compartment. A controller receives input from the sensors, and activates an electric heater or an electric cooler to bring the temperatures within the passenger compartment within a predetermined temperature range if the temperature detected within the passenger compartment falls outside of the predetermined range of temperatures. The controller may automatically shut off the engine of the vehicle when the vehicle is in idle and the carbon monoxide level within the passenger compartment falls above a predetermined level, or if a transmission lever of the vehicle is placed in a park position. A motor generator unit coupled to the engine provides electricity to rechargeable batteries of an alternate power unit, which powers the electric heater and the electric cooler.