Fritz Fleischmann To the Editor: As the cold winter months arrive, many drivers warm up their car in the morning by letting it idle in their driveway; many leave the engine on while parked for short errands. In Massachusetts, this is illegal and can get you a fine of up to $ 500 (first offense: $ 100). In other states, you can be fined as much as $ 1,000 for this practice. The Massachusetts statute (Mass. General Laws, Ch. 90 sec. 16A) prohibits parked idling for more than five minutes, with certain exceptions (when a car is being serviced; when engine-assisted power is required for deliveries). Emergency vehicles (police, fire, medical services) are exempted as well.