What happens if I put the wrong fuel in my car?

Your car needs a certain kind of fuel to run smoothly. If your car requires premium fuel, that usually means above 95 octane. If it needs diesel then it needs, well, diesel. What it doesn’t need is petrol when it runs on diesel. That is not an ideal situation to be in.


You can technically run both a petrol and a diesel on a mixture of both fuels as long as the ratio is extremely high in favour of the preferred fuel. We do not recommend or suggest you do that though.

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

Ok well it depends on how wrong you got it and if you can save it.

For example if your car should run on premium (95 octane or higher) fuel and you’ve put low (like 91) octane fuel in. In this scenario, if the tank isn’t full, you should fill it as high as possible with the highest octane fuel available. Then drive the car gently and try not to put it under too much load.

If you are concerned and if your engine isn’t working/sounding like it should, then do not drive it under any circumstances.

You can call roadside assistance and they will usually have a fuel pump to suck out the poor mixture. It is a lot cheaper than a new engine but not as cheap as taking 2 seconds to check which pump you’re using.

What if I mixed diesel with petrol or petrol with diesel?

Well that isn’t ideal. Do not turn your car on. Do not drive it. Push it out of the way and call roadside assistance. They will pump your tank and save you a serious bill.

If you turn the car on, it will suck the wrong fuel through the fuel pump, through the fuel filter and through your diesels common rails. This is always far more dangerous with a diesel tank as the extremely high octane petrol will destroy the engine.

A petrol engine will not function with diesel but at least it won’t ruin the fuel system.

There’s a problem with my fuel

We can help you sort anything fuel related. One of our talented garage partners here can help resolve any issue. Just click here and book it in for whatever you need, if you don’t know what you need then book it in for a diagnostic.

Don’t be too cut up about putting the wrong fuel in. The filler necks are colour coded but when you have a mind blank all is forgiven. My Dad, who taught me how to drive, has put petrol in his diesel Ute before. He’ll never live it down until the day that I do the same.