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What should you do if you put the wrong fuel in your car?

What should you do if you put the wrong fuel in your car?

If you’ve ever put the wrong fuel in your car, and subsequently felt like an idiot, don’t worry you’re not alone; according to the AA, someone does it every three minutes.

But feeling stupid is a minor issue compared to the damage misfuelling can cause to your vehicle. Whether you’ve put petrol into a diesel car, or vice versa, here’s what to do:

    1. Don’t start your car – This is the most important thing to avoid doing. Starting up circulates the wrong fuel around the engine, which can cause major damage.


    1. Don’t keep the key in the ignition – As some cars start fuel circulation even before the engine fires, keep your key well away from the ignition.


    1. Automatic cars – If you have an automatic, you might be tempted to turn the engine over so you can put the car into neutral and push it away from the pumps. Only do so if there’s no other option and it’s vital that you move it.


    1. Tell the garage – The garage might be able to assist you by making it clear to other drivers what you’ve done; perhaps by cordoning off your car and enacting other emergency procedures. They might even help you push it to somewhere safe and out of the way if you’re alone.


    1. Use your breakdown cover – Call your breakdown cover provider. If you’re lucky, on arrival the mechanic will simply drain, flush and then refill your car’s fuel tank, allowing you to continue your journey. However, your car may need towing to a garage for repairs.


    1. What if it’s too late? – If you’ve driven away from the petrol station, your car will soon let you know something’s wrong and will stop moving. Go through the same procedures you would if you’ve broken down the ‘normal’ way, but don’t try to start the car again.

    Symptoms of misfuelling

    If you’re not sure if you’ve put the wrong fuel in or not, look out for erratic acceleration and a lot of smoke emitting from the exhaust. The car may simply ‘die’ quite soon after driving away from the garage where you misfuelled and the chances are you could have wrecked a good number of key engine parts.

    How much will it cost? If it’s the best-case scenario of a drain and refill, the cost is likely to run into hundreds. However, if you’ve turned the engine over the cost could run into thousands.


    Will your insurance cover you?

    Most breakdown policies cover misfuelling, but don’t forget you’ll have to pay the excess (this varies depending on your policy, but is usually around £150 to £250). At Policy Expert, we offer breakdown cover which includes recovery to the nearest repair centre to drain and flush the engine and add 10 litres of the correct fuel.


    How to stop it happening again

    The best prevention is probably to put a diesel-only fuel cap onto your fuel tank neck (if you’ve got a diesel car of course!). This won’t allow petrol nozzles to fit as they’re a different size to diesel nozzles. If you own a petrol car, the only real answer is to be very careful when at the garage! However, some of the latest cars have sensors which should alert you to your mistake before you pull the pump nozzle trigger.


    Policy Expert

    The customer service team at Policy Expert is always on hand to help – either online or over the phone. Whether you want assistance in finding the right policy or even handling a claim, we make sure it’s all handled by experts. For more information on what‘s covered under your Car Insurance policy, you can call our experts on 0330 0600 600 or visit for more ways to reach us.

    Published 29 January 2018