What to do if you put the wrong fuel in your car


It’s a last-minute panic we all experience when reaching out for the fuel pump at the local garage. Is it petrol or diesel? Surprisingly, there are over 150,000 brits that carry out the mistake of filling their vehicle with the wrong fuel each year and so we are here to provide you with the vital steps to take post-error, to ensure that both you and your vehicle remain safe.

It is important to remember that keeping your ignition switched off will allow way for a safer fix. However, not all of us realise our mistake until payment has been made and we are back in our vehicles with the ignition switched on. This simple action results two very different follow-up approaches to be taken. Allow us to walk you through them both.

If you have not tuned on your ignition since the error, follow these steps:

  1. By keeping your vehicle switched off, you are allowing yourself to remain in the luckiest possible position at this point, so be sure to keep your keys away from the ignition to avoid the habit of switching it on. Act fast with the following steps.
  2. At this point, you must alert staff at the petrol garage of the situation. They may be able to offer aid with step 4.
  3. Ensure your car is in neutral. If you need to make a change to the gear, do this whilst the car remains switched off, with your keys away from the ignition.
  4. With assistance, carefully push your car to a nearby safe place, out of the way of traffic and any other petrol pumps.
  5. Once your car is in a safe place, call your insurance provider or, if local, your MOT station. These providers should be able to visit you on a call-out to drain and re-fill your vehicle with the correct fuel, allowing you to continue with your journey safely.

If you have turned on your ignition since the error, follow these steps:

  1. Depending on the length of time that has passed since filling your vehicle with the incorrect fuel, your car may alert you of your error before you realise, by grinding to a harsh stop. If you become suddenly aware of your mistake before this action occurs, pull over and switch your ignition off as soon as possible.
  2. Once the ignition is off, ensure that your car is in neutral. If you need to alter the gear, do this with the car remaining switched off and with the keys away from the ignition, ensuring that you don’t switch it on out of habit.
  3. As you may have pulled over on a roadside, be sure to remove yourself from the perimeters of your vehicle and into a safe spot away from any passing traffic.
  4. Make a call to your insurance company as soon as possible. They can then attend to your vehicle on a call-out to drain your tank, flush it through and check for any further damage that may have occurred, before refilling your vehicle with the correct fuel.

Even if you are confident with your fuel choice at the time of filling up, you may remain weary or unconfident when driving away from the garage. If your choice was incorrect, there are several indications that you may encounter. If you don’t come across any of these signs, you are most likely safe to drive with the correct fuel within your vehicle.

If you mistakenly put petrol into your diesel tank, you may notice:

  • A knocking sound each time you accelerate. Your acceleration will therefore become sluggish.
  • Darker and more excessive smoke appearing from your exhaust, visible in your rear-view mirror.
  • A warning light appearing on your dashboard, signaling that something is faulty with your car or its engine.
  • Your vehicle coming to a harsh stop on the road.

If you mistakenly put diesel into your petrol tank, you may notice:

  • Your engine may fail to turn, or cutting out after driving a short way, then failing to restart.
  • Darker and more excessive smoke coming from your exhaust, visible in your rear-view mirror.

If you require any further information on how to recover your vehicle after a fueling error, or any other queries about the function of your vehicle, do not hesitate to get in touch with our team at Bromley Vehicle Test Centre by calling 020 8460 6666 where we will be happy to help.