The short answer is no. Back when we had to use the choke when we started the car we let it run for a few minutes or it would stall when we put it in gear. Old habits die hard , and some people still feel the need to let their cars idle to warm up, but modern engines with fuel injection make it unnecessary. In fact, after 30 seconds the oil in the car has already had a chance to circulate, that’s all the time it takes to check your mirrors and go.
The Ten Second Rule
According to the Environmental Defense Fund, drivers should turn off their ignition if they will be stopped for more than ten seconds. They helped debunk the myth that you burn more fuel turning off your engine and back on. After ten seconds of idling you waste more money if you leave the engine running. Shutting off the engine will save money and lower emissions.
The car warms up faster if you drive it, so the simple fact is that letting it warm up is burning extra fuel and wasting money. Not only that, you may be shortening the life of your engine because idling causes your engine to run inefficiently, and gas rich. Over the lifetime of your car this means unnecessary wear on the engine, and poor mileage. It is estimated that over the course of a single year, you will waste 20 gallons of gas if you idle for only five minutes a day. This equates to about $70 – in my zip code – plus about 440 lbs of carbon dioxide emissions. Drive gently for the first few minutes, and go easy on the brakes too, they need to warm a little so you don’t warp the rotors, since they will go from zero to about 200 degrees if you slam them on.
Letting your car idle in the driveway or garage to warm up the interior can be a dangerous habit. Having already lost a family friend to accidental carbon monoxide poisoning, I try to help spread the message that this odorless gas is extremely dangerous in closed spaces. Even with the garage door open, carbon monoxide can build up, and even enter the house. Carbon monoxide is not the only concern though. The fumes from exhaust are toxic to pedestrians and have been linked to cancer, heart and lung diseases, asthma, and allergies, especially in children. Look out the window when you are idling at the curb, and you’ll see children in strollers passing by on the sidewalk breathing in the poison.
The Best Option For Cold Weather
If you live in a cold climate and need to warm the engine to get it to start, get an electric block heater that works on a timer so you can program it to warm the engine and hour or two before you need to drive.
Joshua Reynolds works for Nissan auto in the sales department. He understands the importance of driving safety and recently wrote about the dangers of carbon monoxide poisoning.