Unleaded in a diesel car – What To Do

Misfuelling is more common than you might think; find out what to do if you put unleaded in your diesel car or vice versa

Putting the wrong fuel in your car may seem unlikely – and if it does happen to you, you may feel you’re the only one who would make such a mistake. However, statistics show that someone puts unleaded in the diesel car or vice versa on average every three and a half minutes, so this is far from the truth!

There’s one main thing to consider if you do put the wrong fuel in your car: DON’T SWITCH ON THE IGNITION. You can save yourself a lot of time and money by not turning the key.

Of course, this advice is only applicable if you realise you’ve used the wrong fuel immediately after doing so. Otherwise, you probably found out the hard way when your car spluttered to a halt at which point it’s already too late.

If you did manage to catch your mistake before switching on the ignition, you just need to get your fuel tank drained. How straightforward this is may depend on your circumstances as well as your breakdown providers. Companies such as the RAC and AA offer a roadside fuel drain; so if you’re covered by them and in a vicinity they cover just give them a ring and they will come to your aid. Alternatively, you can ask your breakdown provider to take you to the nearest garage. If you’re not covered by a breakdown provider, don’t panic – all major breakdown providers cater to non-members for a fee.

In the more unfortunate event that you did switch your ignition on, the process for getting your car back on the road can be more complicated. To fully diagnose the damage and get your car back on the road, you’ll most likely need to be recovered and have your car taken to the nearest garage. If you’re Oxfordshire, we at Highfield Motors Ltd will be happy to help from our well-equipped repair shops.

Unleaded in a diesel car

This is the most common type of misfuelling, as the unleaded nozzle fits easily into a diesel hole as the diesel hole is larger. Diesel acts as a lubricant, helping the mechanisms in the fuel pump slide smoothly over each other. When mixed with petrol, it becomes more like a glue – and of course has the opposite effect. The more unleaded pumped through a diesel car, the worse the damage. You may need major parts replacing if a large amount of fuel has been pumped through. It may be worth checking with your insurance company whether or not this is covered before getting any work done.

Diesel in a petrol car

This is a less common problem as the diesel nozzle is typically larger than the petrol filler hole. However, it does still happen, and while the damage may be less severe, it is still important to get your tank drained as soon as possible.

Tips for avoiding misfuelling

•Rather than relying on colour, check the label on the nozzle. There’s often a label on your filler cap, too – you can double check these match for your full peace of mind.
•Avoid refuelling in a hurry or tizz
•If you’ve recently swapped from petrol to diesel, leave yourself a reminder such as a post-it note on the dash.

Added: 31 August 2016