It's tempting for drivers to fire up the motor on a chilly, icy morning and then pop back inside to make a coffee. Indeed, getting your car warmed up on your drive or roadside is something countless drivers will do during winter.

However, this behaviour could land you in hot water. According to Regulation 98 of the Road Vehicles (Construction and Use) Regulations 1986, it is an offence to leave a vehicle's engine operating unnecessarily whilst stationed on a public highway. This means if you're spotted seated in your motor, or even positioned alongside it, with the engine ticking over to clear ice from your windscreen, you face an £80 penalty, reports the Daily Record.

Neil Hutchinson, founder of JLR Essex, describes it as amongst the most frequent winter blunders motorists commit. He said: "Everyone's guilty of it. You wake up, it's freezing, and you start the car to warm it up while you finish your coffee.

"But if you're parked on the road with the engine running, that's technically breaking the law. It might seem harmless, but councils and police do issue fines for it, especially outside schools and busy streets."

Whilst some people believe idling helps the engine during frosty mornings, modern vehicles are designed to be operated almost straight away. Neil added: "Engines actually warm up faster when you're driving, not idling. Leaving the car running just wastes fuel, adds wear to the engine, and risks a fine on top of it."

As well as this, motorists are being urged not to abandon vehicles unattended with keys left inside, a primary factor behind 'frost jacking', where criminals target idling cars left to defrost. Instead, specialists recommend using a scraper or de-icing spray, ensuring all windows are clear before departure, and driving cautiously for the initial few minutes to allow the engine to warm up naturally.

Neil said: "It's a small change that can save you fuel, protect your car, and keep you on the right side of the law. It's just not worth an £80 fine for a few minutes of warmth."

To tackle the ice, some people also resort to convenient shortcuts. Nevertheless, some of these approaches pose concealed dangers, and a motoring specialist has cautioned against one widespread technique that could be causing serious damage to your vehicle.

Robert Webster from MyCarGlass, said: "More TikTok hacks are going viral as users share quick-fix solutions to common problems. One of the most recent includes using boiling water or salt water to defrost car windows in winter, but this could actually do more harm than good.

"While boiling water might seem like a quick and easy solution for your frosted car windows, it could cause drastic damage to your car. This is because the drastic temperature change between cold glass and boiling water results in thermal stress, which could crack or shatter the glass."

Little known driving rule that could lead to fines on cold mornings | Bristol Live