What is vehicle idling?


written by Carmen Fong

What is vehicle idling?

         Idling is when a driver leaves the engine running when the vehicle is in park or not in motion.


Why is idling important?

         Idling can affect three important factors:

  • Fuel consumption: idling causes significant amount of avoidable fuel usage.
    o   For example, idling for one hour can use up to a gallon of fuel
    o   Idling also increases the number of maintenance required from wear and tear
  • Carbon emissions: burning fuel uses up natural resources and increases emissions which affects the environment.
    o   In addition to carbon emissions, vehicles produce methane, and nitrous oxide from tailpipe emissions
    o   Carbon emissions is a principal greenhouse gas that contributes our current climate change
  • Health of individuals: vehicles left idling leave negative impact on individuals
    o   The main component in gasoline is carcinogenic, which promotes cancer. As a result, damaging lung tissue, worsen lung disease, and decrease our body’s resistance in respiratory infection.


Most states within the United States don’t allow idling, but it can be hard to understand and process this information. The air quality within the United States is still healthy and low. But with no actions taken, our environment can end up like others, where it may be difficult to repair.

A recent study on China’s air quality proved that Beijing remained as the city with the worst air quality. The main factor that affected this was their regulations towards emissions, ranging from vehicles to plants. Unhealthy air quality affects not only affect our health but our social lives. The brown haze that surrounds Beijing has affected its community and created a condition called the “Beijing cough,” a dry hacking that accompanies with an itchy throat. Beijing’s air quality can trigger short-term affects ranging from heart attacks to bronchitis, with long-term effects such as lung disease or birth defects. Currently L.A. has one of the worst air quality in the United States, Beijing is 10 to 20 times worse than L.A.

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California Regulations for Idling

Idling can drastically effect our environment and our health. To prevent this from happening, over 30 states in the United States have made idling illegal with specific restrictions.

Under the vehicle code section 22515, vehicle must not be left unattended when stopped or parked. If a vehicle must pull over to the shoulder on the highway, they are advised to turn off their engine to prevent unnecessary idling.

In 2016, the California legislature took an important step on student health and idling by adopting ACR-160: motor vehicle idling: children. The measure encourages motorists to stop idling around places where children are present, such as public schools.

California’s anti-idling law allows vehicles to idle for a maximum of 5 minutes. Vehicles that idle longer than 5 minutes may be subject to affine of $300 with penalties ranging from $1,000 to $10,000.
         Exceptions to this law include:

  • Traffic conditions
  • Adverse weather conditions or mechanical difficulties
  • Vehicle safety inspections
  • Prevent safety or health emergency

Commercial vehicles must also follow the California anti-idling law, but can idle in situations such as:

  • Operating a power-take off device
  • A bus with passengers on board or idling for up to 10 minutes prior to boarding
  • Truck’s engine meetings the optional low-NOx idling emission standard and is located more than 100 feet away from restricted areas

California is doing great by creating policies and regulations regarding idling, but these regulations are still unknown towards the public. Vehicles will still idle in front of schools, residences, drive-thru’s and every possible situation we can think of. To reduce carbon monoxide emissions, the state has been actively promoting and encouraging people to purchase alternative fuel vehicles with incentives to purchase these vehicles. Larger automotive companies such as Audi, Ford, and BMW are also taking action by implementing “start-stop” technology in their newer model vehicles.

But.. the promotion of our idle-free program relies on the community through pledges and word of mouth. The Pittsburg Unified School District (PUSD) was the first district in the East Bay to create “idle free zones” to encourage staff and parents to be idle-free at work and schools. Other states such as North Carolina allows public and private schools to post idle-free signs in parking areas and school driveways.



It’s time to start thinking about idling and how it affects our community.

  • Warming up a vehicle only takes up to 30 seconds, even in cold weather
  • Leaving your vehicle running is more damaging than turning your car off
  • 10 seconds of idling wastes more fuel than restarting your vehicle

12 million gallons of fuel is wasted by idling in the US every day! That equals to 387,000 barrels of foreign oil imports AND $32,680,000 spent.

Click here to learn more about the idle-free campaign.



Smart-Stop Technology

Start-stop technology is an anti-idling technology that automatically turns the engine off when the vehicle is stopped and immediately restarts when the driver accelerates or lifts off the brakes.

Start-stop technology helps reduce idling and the emission of carbon-monoxide gasses and helps save fuel by switching the engine off when a vehicle is idling.

Does smart-stop technology cause more wear and tear?

Most wear and tear from a vehicle comes from the starter of a vehicle. Starters for a vehicle will last up to 50,000 start cycles (from starting the vehicle to turning it off), but with the smart-stop technology, a vehicle will be responsible for over 500,000 start cycles. To prevent or limit wear and tear from this process, automakers created a special starter to handle the stress better. Recently, Denso, an automotive manufacturer, partnered with Toyota to create the “Permanently Engaged” starter. As the name suggests, the starter will eliminate any lag time when a vehicle needs to be restarted.

Auto smart-stop technology are available in most hybrid vehicles and certain conventional vehicles such as Audi, BMW, and Mercedes-Benz.


What if I have an older vehicle?

Auto start-stop technology is very limited to older vehicles due to the technology that comes with it. But a recent company has created a system to help older vehicles integrate new technology with a tool.

Voyomotive, a technological company is hoping to develop automotive technologies to increase safety, security, and fuel efficiency for newer generations.

Voyomotives has developed Voyo, a telematics system that taps into a vehicles diagnostic system and allows its users to perform various activiities ranging from auto-start to stop system to providing cloud-based security.


Voyo’s EcoStart is an idle-free feature that allows drivers to control when a vehicle shuts off when it is idling. Voyo also keeps track of basic statistics showing how much they saved on money, gas, and CO2.

Voyomotive has also developed a prototype anti-idling free system for heavy-duty vehicles. Heavy-duty vehicles such as truckers often leave their engine on idle overnight to maintain a certain temperature and to charge the battery. The new prototype will monitor parameters such as cabin temperature, battery levels and automatically start and stop the engine to keep it within limits.

Take the pledge and become idle-free!

Spread the news and promote anti-idling by sharing this via social media, and notifying others about the changes they can contribute to our community.

For more information about idle reduction and the idle-free campaign, contact Troy, Clean Cities Coordinator, at troy@lungsrus.org.