Discover why the winter morning ritual of warming up your car is a costly myth that damages your engine.
It is a chilly June morning across Australia. You step outside, breath pluming in the cold air, start the car, and crank the heater. Then, you head back inside for a coffee while the engine 'warms up'. For decades, this behaviour has been a staple of winter motoring. But automotive engineers and fuel experts agree: idling your car in winter is not only burning a hole in your wallet, but it is also actively causing long-term damage to your engine.
As we navigate June 2026, the global energy landscape remains complex. While Australian motorists have seen some relief at the servos—with pump prices stabilising after alternative supply chains bypassed recent Middle East disruptions—the market is still highly volatile. The UAE’s dramatic exit from OPEC last month, followed by the OPEC+ decision on June 7 to adjust production quotas by 188,000 barrels per day starting in July, means international crude prices could shift at any moment. Domestically, the federal government is facing intense pressure from the tourism sector to extend the fuel excise tax cut beyond its looming deadline ahead of the July school holidays. With such uncertainty alongside the rising costs of insurance and rego, wasting fuel on your driveway is a luxury few can afford.
The idea that an engine needs to sit idle for five to ten minutes before driving is a hangover from the days of carburettors. Older cars relied on mechanical carburettors to mix air and fuel, and they genuinely needed time to reach the right operating temperature to prevent stalling. However, modern vehicles built in the last 30 years use Electronic Fuel Injection (EFI). Your car's computer sensors instantly measure the ambient temperature and adjust the air-fuel mixture to compensate for the cold.
When you idle a cold engine, the system runs 'rich', meaning it pumps extra petrol into the combustion chamber. Because the engine is just ticking over at idle, it doesn't generate enough heat to fully vaporise this extra fuel. This leads to a phenomenon known as 'cylinder wash'. The unburnt petrol washes the crucial lubricating oil off the cylinder walls, increasing friction and causing premature wear to the piston rings and cylinders.
Furthermore, idling leaves your exhaust system cold. As the rich fuel mixture burns, it creates water vapour. In a cold exhaust pipe, this vapour condenses into liquid water, which pools in the muffler and catalytic converter, accelerating rust and corrosion from the inside out.
With household budgets already stretched, every drop of fuel counts. When you idle your car, you are getting exactly zero kilometres per litre. Let's look at the current state of play at servos across the country to understand just how much this habit might be costing you.
Nationally, U91 prices currently range from 141.9 cpl to 159.5 cpl nationally, a difference of 12.4%. If you're looking to minimise your winter fuel bills, you might be lucky depending on your postcode. The top 3 cheapest capital cities for Unleaded 91 are currently Adelaide (153.89 cpl), Sydney (157.2 cpl), and Perth (157.6 cpl). In fact, Adelaide currently offers the cheapest prices for 4 different fuel types, making it Australia's most affordable capital city for motorists.
However, regional motorists and those in specific capitals are feeling the pinch even more. Unleaded 91 prices are 10.8% higher in Townsville (170.52 cpl) than in Adelaide (153.89 cpl). For those running high-performance vehicles that require premium blends, Premium 98 prices vary significantly across Australia, with Darwin (197.54 cpl) being 10.3% more expensive than Adelaide (179.13 cpl). Even within the same city, the premium tax is clear; in Sydney, Premium 95 (174.33 cpl) costs 10.9% more than Unleaded 91 (157.2 cpl).
Tradies letting the ute warm up on a frosty morning are also burning cash unnecessarily. Diesel is currently 12.7% more expensive in Hobart (202.16 cpl) compared to Newcastle (179.3 cpl). While some drivers try to offset costs at the pump—for instance, Brisbane motorists can save 1.5% by choosing E10 (159.55 cpl) over Unleaded 91 (162 cpl)—those minor savings are quickly vaporised by unnecessary idling.
For those with alternative setups, LPG (avg. 115.8 cpl) remains 22.5% cheaper than Unleaded 91 (avg. 149.5 cpl), offering significant savings for vehicles with dual-fuel capability. Meanwhile, in the commercial and alternative sectors, Nationally, B20 (avg. 289.9 cpl) is 544.2% more expensive than EV (avg. 45 cpl), underscoring the stark contrasts in running costs across different powertrains.
To protect your engine and your wallet this winter, adopt these simple, expert-approved habits:
While cutting out the morning idle will save your engine from premature wear, tracking down the best fuel prices is the ultimate way to keep your motoring costs down. That is where FuelRadar comes in. Offering real-time fuel prices Australia-wide, the FuelRadar app helps drivers find the cheapest fuel nearby, ensuring you never pay more than you have to at the pump.
Available on iOS and Android, FuelRadar is designed to be your co-pilot through the unpredictable cycles of the fuel market. Whether you are driving a petrol hatchback, a diesel ute, or a dual-fuel SUV, you can easily compare prices and plan your journey. You can even check out our interactive map right now at FuelRadar Map. Download the app today, stop the idle, and start saving!
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