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Driving advice

The ultimate summer car myths - busted

We're always a bit doubtful that summer has arrived, but when it does, we totally embrace it. Well, we'd be mad not to - it only last for a few weeks!

The trouble is, reports of what summer 'can' do to our cars causes unnecessary worry. From paintwork issues to tarnished dashboards, we're told that summer is our car's enemy.

Happily, this is absolute tosh; the heat in the UK rarely reaches temperatures which can harm your car. Here are seven summertime car myths we've busted so you can carry on, safe in the knowledge the only issues you'll have are funny looks when people hear your 'In the Mix '96' playlist.

Myth: You get less petrol for your money when it's sunny

This is an oldie but goodie; many people believe that as the day goes on and the heat rises, petrol expands in the tank underground at the forecourt. So, when you fill up, you'll get less fuel for your money.

This gave rise to the myth that filling up in the morning when it's cooler is more economical.

Our verdict? False. The petrol is kept underground where the temperature is cooler and more stable, so you'll get the same amount of fuel when you fill up at any time of day (or night). No need to keep getting up at 5am to fill the car up, then.

We provide 24/7 roadside assistance.

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Myth: The fuel in your tank will 'escape'

Many people wrongly believe that petrol evaporates quickly in the summertime, and we're left out of pocket by their cars gradually leaking petrol fumes throughout the day.

If this was true, you'd walk through car parks and busy streets and smell nothing but petrol - which doesn't happen. Your car's petrol cap does a great job of keeping the petrol where it belongs. Inside your car.

Car at petrol pump 

Myth: You can't get sunburned behind the wheel

Heads up, everyone - time to reach for the suncream. Even though you're behind glass when you drive, you can still get sunburned. Windows and windscreens will block some - not all - UVA and UVB radiation, which causes burning and increases your risk of developing skin cancer.

Always wear sun block if you're in a convertible (lucky you!) or you keep the windows open to cool down. If you burn easily or drive a lot, you should wear sun cream on a daily basis.

A huge part of keeping your cool when the heat's on is avoiding glare when you're driving. Make sure that you find a pair of sunglasses that block 100% of the sun's harmful UV rays; they needn't be expensive or designer, and they're available in many high street shops such as Boots and M&S.

If you've got prescription glasses with reactive lenses, they won't go darker in the car like they do outside due to the windscreen's UV filters. You might be better off buying a pair of prescription sunglasses for driving.

Myth: The sun will ruin your car interior

If you live in a hot country where you're always parked outside, the sun may eventually fade fabrics and crack or 'warp' plastic interiors.

In the UK, this is unlikely for two reasons. Number one - the UV filters in car windows block the damaging effects of sunlight, and our summers are not fierce enough to have an effect on the average modern car. If you want to use windscreen covers and car window shades, go ahead - they'll make the car much cooler and help keep the steering wheel temperature down. You don't need them to protect your seat covers and fittings.

The temperature inside your car can quickly reach over 40°C in the sun, even if it feels pretty cool outside - so never leave children or pets alone in the car, even for a few minutes.

Myth: The water in your car battery will evaporate

In the past, we were advised to check our batteries for low water levels and to top them up themselves when the weather warmed up. However, car batteries have been sold 'sealed up' for over 20 years, so even on sunny days the water in your battery will stay put.

Car parked in sunny country

Myth: The water in your radiator will disappear

Most modern cars have a sealed cooling system (like your battery), so you won't need to top them up either.

If the level of coolant in your radiator is dropping rapidly, it won't be due to a few days of sun. It's more likely that your cooling system is leaking, either through a hose or the radiator, or inside the engine. A leak into the engine is potentially far more serious, so if you think you've got one, head to your nearest garage.

You should check your engine coolant and coolant fan a few times a year, just to make sure everything's ticking along OK.

Myth: The sun will ruin your paintwork

If you're lucky enough to live somewhere with year-round blistering sunshine (so probably not in the UK then!) this can be a blessing for you, but a curse for the car, as the sun will dull the paintwork and give it a 'chalky' appearance. However, a few days of sun in the UK won't have a huge effect. A reasonably clean and polished car will be fine during a heatwave.

However, bird mess and tree sap are another story. They're hugely irritating as they 'bake' onto hot paintwork and removing them is time-consuming and tricky. Plus, the chemicals in them can damage your car's paintwork.

Our advice is to get rid of them as soon as you can. Soak the mark with a mix of warm water and car wash shampoo, and gently rub to remove it. As far as evening activities go, it doesn't compare to Corrie with a cuppa, but you won't regret sorting out these stains before they set like concrete.

Related advice

  • Debunking driving myths
  • Clever ways to combat hot cars
  • Wrong fuel advice
  • Mobile phones and driving
  • The real cost of running a car
  • Smoking in the car
  • What to do if you break down

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