Motorists warned against warming engines before driving

Motorists have been warned to stop making a common, and very bad habit, or risk wearing out their engine. In the fresh message, consumer champion experts at Which? urged people to ‘stop’ unless you have one specific type of car. And if you continue, you could end up with a fine.

In their post on X, Michael Passingham, a senior cars researcher, was asked whether people should leave their car running to warm the engine up. His answer? “No. Only cars with carburettors need this to be done, and they haven’t been made for more than 30 years. The only exception to this is if you want a nice, clear windscreen and a toasty interior when you get in. Some new cars have apps that you can turn the car on remotely and have the car ready when you’re ready.”

The expert added why it is never advisable to warm up your car engine by leaving it running whilst you wait inside. It states: “While advice varies from manufacturer to manufacturer, it is normally preferable to drive your car gently immediately after turning it on, rather than leaving it to warm up. Not only will the engine warm up more quickly, reducing the potential for engine wear, but you’ll also use less fuel in the process.”

But what if it is cold outside and your car windscreen is frosty? The experts say that if this happens and “your car is iced over, use an ice scraper or de-icing spray rather than leaving your car running and relying on the heating.” In its blog post, the experts further recommend that people take action early. It reminds people getting behind the wheel: “Ensure your car is regularly maintained according to its service schedule.

“Aside from reducing the potential for big bills further down the line, a newly serviced car with clean oil and fresh filters will run more efficiently. Some manufacturers also provide winter checks on their cars, where a dealer will examine your car to check if it’s safe to drive in wintery conditions.”

Which? are not the only experts handing out the same advice. Car experts at RAC Drive have issued a clear warning, revealing that some people could face fines. It noted: “You can be fined for leaving your engine on to melt ice, frost or snow from your car’s windscreen.

“If you fail to turn off your engine when instructed, you may receive a fixed penalty notice of £20. If the driver doesn’t pay this fee, then it will rise to £40 if the £20 is not paid within 28 days. This is increased to an £80 fine if the £40 isn’t paid in the following 14 days. This fine can also be increased to £1000 if you are repeatedly caught doing it.”

It stresses: “Do note, the crucial element of the wording is the reference to ‘public road’, which means it is not an offence to leave your engine running on private land, such as a driveway. However, that is not to say that allowing an engine to idle is a good idea.”

While this means people who park on a public road, for example, those living in flats with no designated parking bays, may be at risk, RAC further adds that even if you have it running on your own driveway, it is not a good idea. This increases the risk of car theft and harms the environment. “An idling engine can produce up to twice as many emissions as an engine in motion, impacting the surrounding the area and the air that we breathe”, it said.

How to de-ice your car the right way

To clear ice from your windscreen, it is a good idea to stock up on a dedicated ice scraper and de-icer. Start by spraying the de-icer onto the windscreen, then use the scraper to remove the ice. Before turning on your wipers, it’s also a good idea to make sure they are not frozen. RAC warns that attempting to use them in this state could damage the motor or tear the blades, which can be costly to repair and with Christmas around the corner, it is the last thing anyone needs.

If you do not have de-icer on hand, there are simple household alternatives you can use. A mixture of water and a teaspoon of salt can be poured over the affected areas, or you can make your own de-icer by combining three parts vinegar with one part water in a spray bottle.

Suggesting to keep a spare de-icer in your car in case it freezes over when you are at work, they warn that drivers should never use a credit card as it could damage your windscreen. You should also never pour boiling water over the windows. It explained: “When the boiling water comes into contact with your freezing cold car windows, it could at the very least weaken the glass and at the very worst cause it to crack.”