Regular unleaded. Premium unleaded. Diesel. There are several options car buyers must choose from. It’s thus no surprise that these get mixed up pretty often.

Now, few things strike fear in our hearts as realising we’ve put the wrong type of fuel in. But, if this is a concern you’re faced with, knowing how to tackle the issue’s vital. We’ve hence outlined some crucial things you should know about putting the wrong fuel type in your car.

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The Problem With Putting in the Wrong Fuel Type

Before progressing, you may be wondering: how much of a problem actually is this? The risks of putting the wrong fuel type in your car is significant. Indeed, while it’s not always simple to mistake petrol for diesel (since the nozzle won’t fit all that easily), putting diesel in a petrol car is an easy mistake to make. Unfortunately, this could put your car at a great deal of risk.

So, how bad is it? To answer this depends on how you tackle the issue. Unfortunately, if you don’t realise – or if you ignore it – then the damage could be severe. If you notice quickly, though, you might be able to get away with it.

What to Do If You’ve Added The Wrong Fuel

If you do notice you’ve added the wrong fuel, there are a couple of steps you should take.

- First, stop immediately. If you are still filling the car, do not add any more of the wrong fuel type. Replace the nozzle and take a moment to breathe.
- Next, consider the car type. If you have a petrol car, check the monitor to see how much diesel you added. If under 5% of total capacity, you may be okay to fill the tank up to full and drive away. However, if you’ve added more than, this, you won’t be able to drive away. If you have a diesel and have added petrol, your option here is simple; it doesn’t matter how much petrol you added.

Don’t drive away. Unless you are within the safe zone of adding diesel to a petrol, you should never drive away. Nor should you turn the car on. This could pump fuel further around the system, causing more damage.

Call out a recovery company. They should be able to drain the wrong fuel from your tank, allowing you to refill with the correct type.

If you are at all unsure or concerned, don’t take a risk. Always get professional support to drain the car; failing to do so could cause significant damage! This is also something you should check for with a vehicle check. Indeed, depending on the severity of the damage, a car could even be written off for this degree of damage, if it is not affordably worth repairing it. So, why risk it?

How Much Leeway Is There?

There’s not much leeway at all when adding the wrong type of fuel to your vehicle. Now, if you’ve put just a tiny amount of diesel into your petrol car, you may be okay. This will depend on how much you’ve added, as it’s generally agreed a maximum of 5% diesel concentration is tolerable. Any more than that, though, and your car could experience damage.

The problem becomes more severe with adding petrol to a diesel car, though. Diesels cannot tolerate petrol contamination, so any petrol in your diesel engine needs to be removed.