Fleet Management

What is Vehicle Idling?

Vehicle idling is the act of leaving the motor engine running unnecessarily while the vehicle remains stationary. It happens when trucks halt with their engines turned on.

Idling is a typical part of driving. Examples include stopping at red traffic lights, getting stuck in traffic, waiting to load and unload some cargo, sleeping in between truck driving breaks, and more.

Truck idling fuel consumption and cost

Engine idling, though common, is disadvantageous to your fuel cost and consumption.

The Department of Energy estimates idling heavy-duty trucks heavy-duty trailers consumes around 0.8 gallons of fuel every hour.

The American Trucking Association also estimates a maintenance cost of $2,000 per vehicle every year due to idling, besides quickening engine wear and tear.

For example, assuming a fuel cost of $3.50 per gallon, a fleet of 20 medium-duty trucks with 10-minute idle periods would waste approximately $15,100 of fuel annually. If you are managing hundreds of trucks, that figure can skyrocket to more than $75,000 a year.

More disadvantages of vehicle idling

Besides ballooned gasoline costs, below are other engine idling disadvantages:

Shorter engine lifespan

Excessive vehicle idling can produce carbon residue build-up in your trucks’ engines. Since the engine is not working at its best temperature while idle, the fuel is only moderately combusted, causing build-up on the trucks’ cylinder walls.

That further impairs engine parts, including exhaust systems and spark plugs, balloons maintenance costs, and shortens the engine’s life.

Environment hazard and health risks

Research by the Argonne National Laboratory, through the Department of Energy, calculates that idling heavy-duty trucks emit around 11 million tons of carbon dioxide, 55,000 tons of nitrogen oxides, and 400 tons of particulate matter.

This impacts air quality leading to pollution and health risks, such as asthma, cancer, and contributing to 4.2 million deaths annually according to the World Health Organization (WHO).


In the US, several jurisdictions have established anti-idling laws and impose penalties for non-compliance (with a few exceptions). These places include Massachusetts, Maryland, New York City, New Jersey, New Hampshire, Louisiana, and parts of Colorado, California, Ohio, New York, Utah, and other states. 

Violation fines can range from $100 to $2,000 in New York City, for instance. In Arizona, transgressing drivers can pay $100 for the first violation and $300 for the second one. Delaware imposes up to $500 for each offense, reaching $5,000 for subsequent acts.

How to reduce vehicle idling

Check these tips to minimize vehicle idling:

1. Use a reliable fleet management software

Robust fleet management tools, particularly those with GPS tracking features, help you monitor your trucks and their conditions and activities. Leverage the collected data and amount of visibility offered by these software apps to lessen idling instances and fuel wastage.

2. Driver training

Educate and train your truckers about vehicle idling, its negative costs and impacts, and technical ways to avoid or minimize it. Establish idling orientation as a regular part of your drivers’ onboarding and training, and coach and supervise them continuously. This helps increase their accountability to your company and relevant state laws.

3. Incentives. Bonuses. Recognition

Rewarding compliant drivers for minimizing idling motivates them to continue doing so. Using fleet management software can help you track these truckers, including those idling the most. Offer least-idling drivers bonuses, incentives, recognition, and other rewards you can integrate into your program.

Vehicle idling myths

Below are some vehicle idling myths that need debunking:

Myth #1: Switching your engine on and off wastes more gas than leaving it running.

Truth: Leaving your truck running for 10 seconds already consumes your gasoline significantly. Compared to idling, stopping and restarting your engine improves your fuel economy. You can save 3% to 5% on average driving. The figure rises to 10% with extended traffic stops.

Myth #2: Idling your truck for several minutes is among the best ways to warm it up.

Truth: Idling is inefficient when warming up trailers, even in freezing weather. A gradual drive on the first mile is the optimal way to heat up your truck’s tires, transmission, steering, wheel bearings, and suspension.

Myth #2: Frequently restarting your engine severely damages it.

Truth: Stopping and starting your engine again leaves little impact on its parts, e.g., the starter and battery. Turning your trucks off delays the engine’s deterioration. Excessive idling harms the internal engine parts.