Let’s be honest, most of us were taught to let the car “warm up” before we drive off. Whether it was Dad’s old bakkie or the family sedan, the ritual of starting the engine and letting it idle for a few minutes felt like an act of care. But we’re not in the 80s anymore, and engines aren’t what they used to be. When you take modern engines, rising fuel prices, and the reality of climate change into account, this habit might just be doing more harm than good. 

Look, idling your car may seem harmless, but there’s a lot of talk about how this action is a silent fuel thief. It costs you money every time your engine runs without moving – and it can wear down your engine over time. In this article, we unpack the real cost of idling and share smarter ways to treat your car (and your wallet). 

The Modern Engine 

The ritual of letting the car warm up in the morning before tootling off to school isn’t based on fairies and old wives tales. The fact is that older engines with carburetors genuinely needed a few minutes to reach optimal performance. But cars built in the last two decades use fuel injection and electronic engine management systems that adjust fuel flow and ignition timing instantly.  

This means that your car is ready to drive within 30 seconds of starting – especially in South African weather, which is rarely cold enough to warrant prolonged warming. 

Going Nowhere Is Expensive 

From our estimations, idling burns between 0.5 and 1 litre of fuel per hour, depending on the size of your engine. We understand that this may not sound like much on the surface, however, if you take a minute to think about your daily routine and factor in your idling over the course of a year, you’ll be surprised at how many litres of fuel you’re burning for nothing. 

Seriously, consider how much fuel you’d burn if your car idles for just 5 minutes every morning. That’s over 25 hours of idling in a year, which translates to around 20 litres of fuel. At R25 per litre (give or take), you could be spending over R500 a year just to sit still.  

Go ahead and multiply that R500 by every household in your neighbourhood, and the impact isn’t so small anymore.  

Engine Damage Is Inevitable 

It’s hard to let go of the idea that warming your engine up is an act of kindness, a seemingly gentle way to treat your car. The truth is, sadly, extended idling isn’t good for modern engines. When a vehicle idles, fuel doesn’t burn completely, and this can cause residue build-up on spark plugs and cylinder walls. Ultimately, this reduces engine efficiency and may lead to more frequent maintenance or repairs over time.  

We don’t suffer from seriously cold weather in South Africa, but we’ve been known to experience a spot of snow and ice in different areas of the country. So, it’s good to know that idling in colder seasons can also cause condensation to form in the exhaust system, which may lead to rust.  

Consider The Planet 

Every litre of petrol burned releases roughly 2.3kg of CO₂. So, if you’re wasting 20 litres of fuel a year on idling, that’s about 46kg of unnecessary carbon emissions. This may seem pretty low for a single vehicle, but South Africa has over 12 million registered vehicles. Even small changes at an individual level can make a big difference in reducing national emissions. 

Feeling Informed? 

There are times when idling is unavoidable, like when you’re in heavy traffic, but generally, we should all aim to reduce unnecessary idling in your daily routine. It’s a small habit shift that pays off over time. 

We trust that this information will help you stay one step ahead. 

If you’re looking for more practical advice, budget-friendly ideas, and planning tools then please take a few minutes to explore AA Inform.