Why Idling Is Costing Your Fleet in Australia — And How to Stop It

Is idling bad for your car? Absolutely. Now imagine an entire fleet sitting idle — the impact on your business’s bottom line can be massive. In Australia, where fuel prices are among the highest in the OECD and compliance pressures continue to rise, reducing idling isn’t just good practice, it’s essential for sustainable fleet management.

In this article:

• What idling means and how engines idle

• The real cost of idling in Australia

• Five reasons to stop idling and the benefits for your fleet

• Four steps to reduce idling using fleet technology

• Practical examples of idling in industries like delivery, logistics, and construction

• How Cartrack can help you save on running costs

Whether it’s drivers leaving engines on while unloading deliveries, stuck in congestion, taking a roadside call, or warming up in winter, every second of idling costs fuel, money, and time. Here’s why idling matters for Australian fleets — and what you can do about it.

What is vehicle idling?

Idling happens when a vehicle engine runs while the vehicle is stationary. Every day across Australia, millions of vehicles idle unnecessarily, wasting fuel and producing emissions.

Common examples include:

• Sitting in stop-start traffic on Sydney’s M4 or Melbourne’s Monash Freeway

• Waiting in drive-throughs or delivery bays

• Running the engine to power air-conditioning or heating during rest stops

For fleet managers, idling is more than an annoyance — it’s a measurable cost driver that can and should be controlled.

How does an engine idle?

On modern fuel-injected vehicles, idle is controlled by the engine control unit (ECU) via the idle air control valve. This valve allows a small, regulated flow of air and fuel into the combustion chamber to keep the engine running when the accelerator isn’t pressed.

While this is necessary in short bursts, prolonged idling is inefficient. The fuel-to-air ratio at idle is too rich, meaning fuel does not combust efficiently. Over time, this can damage spark plugs, clog exhaust systems, and increase engine wear.

The Real Cost of Idling in Australia

To understand why idling is such a problem, let’s break down the costs:

• Fuel use: A passenger car idling uses between 0.6–1.2 litres of fuel per hour. Larger diesel vehicles use 2–3 litres. At an average fuel cost of $2.10 per litre for petrol and $2.30 per litre for diesel (2025 figures), that’s $6–$7 per hour wasted per vehicle.

• Fleet impact: If 20 vehicles idle for one hour a day, that’s around $3,000 wasted per month — or more than $35,000 annually — purely from fuel.

• Environmental cost: Each litre of fuel burned produces about 2.3kg of CO₂. Multiply this across hundreds of hours of idling per year, and the environmental footprint is substantial.

These numbers highlight why idling is one of the easiest and most impactful behaviours to target for cost savings.

5 Reasons to Stop Idling in Your Fleet

1. Less wear and tear on parts
Idling causes more engine wear than running at regular speed. Fuel wash during idle strips vital lubrication, creating friction that accelerates wear on pistons, spark plugs, and exhaust components. An engine idling one hour per day can accumulate the equivalent of tens of thousands of kilometres of extra wear each year.

2. Lower health risks
Idling produces harmful emissions such as nitrogen oxides, carbon monoxide, and particulate matter. Drivers sitting in idling vehicles are directly exposed to these pollutants, which are linked to asthma, cardiovascular issues, and chronic respiratory diseases.

3. Environmental protection
Transport is Australia’s second-largest source of greenhouse gas emissions, responsible for around 19% of the national total. Reducing idling is one of the simplest ways for fleets to cut emissions. For every 10 minutes of idling eliminated, approximately 1kg of CO₂ is avoided.

4. Fuel savings
Reducing idling directly reduces fuel bills. For example, cutting just 30 minutes of idling per vehicle per day across a fleet of 50 vehicles could save more than $75,000 annually in fuel costs.

5. Reduced business costs
Lower idling means reduced maintenance, fewer breakdowns, and extended vehicle lifespans. This lowers capital replacement costs and boosts overall fleet profitability.

4 Ways to Reduce Idling with Fleet Technology

1. Driver behaviour reports
Fleet management software tracks idling, speeding, and harsh driving events. Managers can see exactly who is idling the most and act accordingly, using coaching and accountability tools.

2. Educate and motivate drivers
Many drivers mistakenly believe restarting a car uses more fuel than idling. In reality, idling for just 10 seconds uses more fuel than a restart. Including anti-idling policies in driver training helps build good habits.

3. Route optimisation
Congestion is a major cause of idling in Australian cities. Cartrack Delivery’s route optimisation uses live traffic data to recommend the fastest, most efficient routes, helping drivers avoid bottlenecks.

4. Geofencing
Geofences can be set around depots, worksites, or delivery hubs where idling is common. Alerts notify managers when vehicles spend excessive time idling in these zones, creating accountability and reducing waste.

Industry Examples: Idling in Practice

Delivery fleets
Couriers often idle while unloading or waiting at customer sites. Monitoring idling ensures drivers shut off engines when safe to do so, cutting wasted fuel in high-frequency delivery operations.

Construction fleets
On worksites, heavy equipment and service vehicles can idle for long periods unnecessarily. Monitoring idle time in these environments helps reduce one of the construction industry’s largest overheads: fuel.

Field services fleets
Technicians attending customer sites may idle while making calls or using on-board tools. Telematics data provides insights into these habits, enabling managers to enforce anti-idling practices.

Save on Fuel and Fleet Running Costs with Cartrack

Idling may seem minor, but across a fleet it becomes one of the biggest hidden costs. The good news is that it’s easy to address. With Cartrack’s fleet management platform, you can:

• Track idling and fuel use in real time

• Benchmark drivers to identify top and poor performers

• Optimise routes to reduce congestion-related idling

• Set up geofences for idling alerts in common hotspots

• Use dashboards to monitor trends and drive accountability