My Garage
New hero

What should I do if I’ve put the wrong fuel in my car?

By Phil Gardner | March 29, 2023


Why not leave a comment?

See all | Add a comment

Whether it’s down to a recent change in vehicle, or lapse in concentration, misfueling happens. Filling up with the wrong fuel is an easy mistake to make, but it can be rectified. Here’s what to do if you find yourself in this situation.

What should I do if I’ve put the wrong fuel in my car?

According to the AA, somebody puts the wrong fuel into their car every three-and-a-half minutes. It’s just one of those things: a little mistake that can cause a lot of problems. However, if you’ve just noticed that you’ve put the wrong fuel in your car, don’t panic. Here’s what to do next.

What’s the worst that could happen?

In a diesel car the fuel itself acts as a lubricant, but petrol doesn’t have the same qualities. Putting petrol into a diesel-powered car is thus a bigger problem than diesel in a petrol. At the very worst, you could need a whole new engine, although that’s highly unlikely. There’s more chance you’ll need new parts like pipes, fuel pumps, injectors and filters. It’s possible you may even need a new fuel tank. For this reason, it’s important once you’ve noticed that you’ve made the mistake that you… 

Don’t turn the key!

Actually, don’t even put the key in the ignition. If the car is keyless don’t start the car.  If you’ve got the wrong fuel in the car, even turning the car on will get that fuel pumping around and cause all sorts of problems. If you’ve just noticed that you’ve just put the wrong fuel in, now is the time to contact your breakdown service or a mechanic. They can assist you by pumping it out again, then replacing it with the fuel your engine needs. This usually means you’ll avoid damage and hopefully get a less expensive bills.

What if I’ve just driven off?

You’ll probably have noticed that your car isn’t sounding or feeling too healthy. If this is obvious fairly quickly – the chances are it will be – there’s still a good chance you’ve avoided major damage and your breakdown service should be able to help. After that, your car will need an inspection to see if any damage has been done. 

Other misfuelling facts and things to think about

  • It’s harder to put diesel into a petrol car because of the difference in sizes of the fuel nozzles.
  • If you’re used to driving a few different cars, this error is more likely to happen. You can put stickers on the inside of the fuel flap to remind you what fuel the car needs. Many modern cars have these already.
  • Don’t lose concentration or get distracted at the pumps. This is most likely what causes a misfuelling error.
  • Remember, if you’ve made this mistake, you’re just one of around 150,000 who’ve also done it this year. It’s more common than you think.

Related Articles

Top 5 most common car problems and how to fix them yourself
DIY Fixes for Common Car Problems: Take Charge of Your Vehicle's Maintenance
Which brand gives you the longest warranty?
Warranties cover mechanical mishaps that aren't your fault and mean hefty bills won’t come your way should something go wrong.
Car safety checks for home: fast, simple, essential
Make sure your car is ready for anything via simple, quick, intuitive safety checks you can do at home.
Halfords speaks out about proposed MOT delay – but what do you think?
Halfords says 225,000 potentially dangerous vehicles would be on the road