You’re actually wasting money by leaving that car idle!
When you’re picking up a friend, waiting inside your car by the curb, what’s the most efficient thing to do? Does it take more gas to start a car or leave it running? It was previously believed that keeping your car idle, instead of restarting your car, is better for your engine. But with new developments in car technology and fuel efficiency, that’s not the case anymore. Idling or restarting have different effects on both your car and the environment. Here’s what you need to know.
Idling is Bad for the Environment
According to a video published by The Massachusetts Department of Energy Resources, keeping your car idle is actually terrible for the environment. The reasoning has to do with the technology used to fuel the engine within the car and how that technology has changed.
“Idling constitutes a significant environmental polluter even though it operates without visible emissions. The exhaust emissions from even a short period of engine idling are harmful, ” says car expert Alan Gelfand.
Back in the day, cars used carburetors to help fuel the engine. Carburetors combine air and fuel for proper engine performance. It also uses more fuel when engines start up, versus idling with the car on. Hence why people keep the car idling to save energy.
However, technology has changed, and carburetors aren’t used anymore. In the 1980s, auto manufacturers switched carburetors out with fuel injection systems. This system also combines air and fuel, but in a more controlled volume compared to a carburetor. The fuel is used more efficiently since little fuel is actually used to start up the car.
Restarting Your Car Uses Less Fuel
More fuel is used when the car is idle, versus starting it up all over again. Hence why we see more cars made with the start-stop technology. Not only does this technology save the overall energy within your car, but it also decreases the amount of wasted fuel (and air pollution) each year.
“Modern engines produce minimal emission spikes during engine restarts while producing zero emissions during engine shutdown so stopping the engine remains the most environmentally friendly choice,” says Gelfand.
“The practice of brief engine starts and stops used to strain starters and batteries, but contemporary vehicles have built-in protection against this practice,” says Gelfand. Although the technology has improved, and fuel-injection systems have proven to be better for the engine, it’s still helpful to point out how continually stopping and starting your car more than 20 times a day could impact car’s battery and starter, according a study by Argonne National Laboratory for the U.S. Department of Energy.
The report concluded that best practices are to limit start-stop events to 10 a day, any shutdown greater than a minute will result in cost savings and drive greater than 5 miles between start-stop events.
So instead of keeping your car idle, shut it off while you wait for that person to hop in!
FAQs
Is idling the same thing as remote starting my car?
Idling is when the car is running without moving. So, if you remote start your car and let it run for more than 10 seconds, it’s the same as idling. If you remote start your car as you walk towards it, then get in and start driving immediately—the car didn’t sit stationary long enough to be considered idling.
How long of a stop is “idling”?
“Any time your vehicle remains stationary for more than 10 seconds with its engine operating constitutes idling,” says Gelfand. “Beyond this time point the fuel consumption of modern engines surpasses the amount needed for a restart. The outdated principle that restarting a car requires more fuel than leaving it in idle does not apply to vehicles produced within the last twenty years.”
About the Expert
- Alan Gelfand has been the owner of German Car Depot for more than 30 years. His business is an independent automotive service center in Hollywood, Florida, specializing in the service and repair of German vehicles.
