Drivers desperate to reduce their fuel costs could try out a money saving hack that actually originates from the Highway Code.
Saving money on petrol is a prerogative for many motorists as costs continue to spiral.
Refuelling at the petrol station is more dear than ever as the cost of petrol surpassed £1.60 a litre for the first time last week.
Costs have already inched past that record-breaking costs, with the RAC reporting the average unleaded petrol price is £1.63 today.
Meanwhile, diesel prices are even higher and are predicted to hit an eye-watering £2 by the end of next month.
To save £150 yearly, one expert has shared one tip that could shave off a decent sum, Wales Online reported.
If your petrol costs are making you wince, you might want to look up rule 123 in the Highway Code and cut out idling your engine.
MotorEasy founder and CEO Duncan McClure Fisher said: "One thing many people do that is entirely unnecessary is to leave their engine idling.
"This can be done first thing in the morning to 'warm it up' or when stuck in traffic. Even dropping off something at a friend’s house can see people leave the motor running instead of turning off the ignition.
"While this might seem very innocent, research has shown an idling engine can burn through 3-4p of fuel a minute.
"If you are doing 10 minutes of warming up, five days a week, and spending another 30 minutes per week stuck in traffic – that adds up to a very handy £166 a year that's being wasted."
As well as saving money, Mr McClure Fisher highlighted that idling engines are bad for the planet and against the law.
He added: "Rule 123 of the Highway Code states, 'You must not leave a vehicle engine running unnecessarily while the vehicle is stationary on a public road'.
"This is enforced under Section 42 of the Road Traffic Act 1988, with local authorities able to issue a fine of up to £80.
"It's obviously not great for the environment to have increased emissions escaping into the atmosphere either."
A 2020 study found that a whopping 60 per cent of UK motorists were unaware it's illegal to sit in a stationary vehicle while the engine is running.
The research, by car giants Renault, also discovered male drivers were 50 per cent more likely to leave the engine running on the school run than females.
The idling rule is one of a host of lesser-known regulations set out in the Highway Code that have the potential to catch people out.
Others include sleeping in a car when drunk, beeping your horn whilst stationary and paying at a drive-through with a mobile phone.
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