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Putting the wrong fuel in your car is a common but expensive mistake to make. Find out whether car insurance could help cover the cost.
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Misfuelling means putting the wrong type of fuel into your car. This typically happens when you’re not paying attention at the petrol pump.
Figures from the RAC suggest that around 150,000 UK drivers make this potentially expensive mistake every year.
It normally involves diesel cars being filled with petrol, which causes more serious damage. Petrol cars aren’t often affected because the bigger diesel nozzles don’t usually fit.
Misfuelling cover isn’t often found as a standard feature of car insurance – out of 325 comprehensive car insurance policies on Defaqto, only 14% cover misfuelling as standard.
Only 2% of the policies could provide misfuelling cover as an optional extra, so you might not be able to add it to your cover, even if you want to..
If you’re covered, it could pay for the cost of draining and flushing your tank. Some policies may also cover the cost of repairs needed because of misfuelling, but it’s important to check and make sure.
According to the RAC, the wrong fuel is put into cars in the UK around once every three minutes. But unfortunately, the cost to drain petrol, make repairs, and replace fuel could add up to as much as £5,000 in extreme cases.
The right cover could help to pay for this potentially expensive mistake.
If your policy doesn’t cover misfuelling, you may be able to buy it as an optional extra. Otherwise, you might want to shop around for a policy that offers this type of cover.
Your car is designed to use a specific type of fuel, so putting the wrong one in it can cause major issues. The problems start as soon as you turn on the engine:
This is the most serious type of misfuelling. Unfortunately, because the smaller petrol nozzles fit easily into diesel cars, it’s much easier to put the wrong fuel into this type of car.
Petrol is more corrosive than diesel and as it moves through your car it dissolves the diesel lubricant which keeps parts moving smoothly.
This increases the friction between parts, which in turn can cause severe damage. In more serious cases, you could even find yourself having to replace the car’s entire fuel system.
Because nozzles on a diesel pump are usually bigger, they won’t often fit in modern petrol cars. However, if you do manage to use the wrong fuel, the damage is usually much less serious than if you’d put petrol into a diesel car.
Diesel doesn’t ignite as easily as petrol, so you may find the engine won’t start or it cuts out. It can also cause an unusual amount of white smoke to come from your exhaust.
This new type of ‘greener’ petrol is becoming more common at petrol stations, but it isn’t compatible with a small number of older cars.
In these cases, the car may still run but the E10 fuel can start to damage some of its parts over time. You can check whether your car can take E10 petrol on gov.uk.
If you accidentally use E10, there’s usually no need to drain the tank - instead, just fill the car up with the right type of fuel as soon as possible to dilute it in your car’s system.
However, if you’re unable to start your car after using E10, call a recovery service.
When you’re looking into whether to buy misfuelling cover you should factor in:
Yes, unlike car insurance - which doesn’t usually include misfuelling cover - most breakdown policies will cover the cost of draining your car’s fuel tank and taking it to a garage if needed.
You might have breakdown cover as part of your car insurance or as standalone cover, so check to see whether you’re already covered.
Although misfuelling cover can help if you accidentally use the wrong fuel, you may be surprised to find out that some policies won’t cover you for:
Unfortunately, putting the wrong fuel in your car is easily done and can be caused by several reasons, including:
Take the keys out of the ignition to make sure this can’t happen
The staff can help you manage the situation and put safety cones out if needed
Put the car in neutral and push it to a safe place
You’ll need a specialist to drain and flush your fuel system
If you’re covered for misfuelling they may have a procedure you need to follow to repair your car
Putting the wrong fuel in your car can be a major hassle, so here are our top tips to help you avoid it:
If you need to make a claim, you should contact your insurance provider as soon as possible.
Before you call, check you’re covered for misfuelling and have your policy number ready.
Gather any breakdown or repair receipts you have as a result of the misfuelling - you may need to use these as proof.
Just like any claim you make on your car insurance, a claim for misfuelling is likely to push up your premiums when it comes to renewal.
You’ll need to balance how much the recovery and repairs will cost you, after any excess is applied, to decide whether it’s worth claiming.
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[1]Last checked 3 January 2023