Putting petrol in a diesel car can have serious consequences, often causing damage that isn’t covered by your warranty. 

Typically, car owners know what to put into their cars, however, sometimes when traveling or borrowing a car, things can get mixed up. 

Here’s what to do if that happens to you: 

What Happens if You Put Petrol in a Diesel Tank?

  • If you are still at the pump:

 Don’t panic. Obviously, do not start the car if you haven’t already.

You should also be particularly careful about the location of the keys. Some newer cars take the key being put in the ignition as a signal to prime the engine and get ready to drive.

And, if you have a keyless entry or a vehicle with a push-button start feature, be careful about the location of your key. This is because you wouldn’t want to accidentally trigger a situation in which you might cause more damage. 

Next, call roadside assistance, put your car in neutral, release the hand brake, and get someone to help you push it away from the pumps to a safe parking spot.

  • If you’ve already driven away

Stop the car as soon as you can safely do so and immediately turn off the engine. Each moment the vehicle remains turns on can significantly increase the damage. 

Once stopped, call roadside assistance. Don’t try to siphon anything out of the tank because you won’t be able to get all of it this way and still risk causing damage to the vehicle. 

How To Avoid Disaster

Usually, problems occur when you are driving a vehicle that isn’t your own. When you are filling up an unfamiliar vehicle, don’t just look at the colours on the pumps, but actually stop to read the words on them.

A diesel nozzle simply won’t fit into the filler gap of a petrol-engined vehicle, but don’t always rely on this as a way to avoid disaster. 

You should also ensure you’re aware of what kind of car you’re driving before you go to fill up. If you aren’t sure just by looking, there is typically a label on the inside of the filler cap that says “Diesel only”, “Unleaded only” or even “Premium unleaded only”. 

If you’re still confused (or if there isn’t a label!) don’t just guess and potentially cause yourself lots of trouble. Ask the service-station attendant for help, call the rental company, or event check the manufacturers guidebook, if it’s in the vehicle. 

Big Differences Between Petrol and Diesel 

If you put petrol in a diesel car, it can cause serious damage to the fuel injection system and the engine. This is because a diesel fuel pump operates on very fine tolerance at high pressures. It is also lubricated by the diesel fuel. 

If you add petrol instead, there isn’t as much lubrication and the fuel pump can be damaged by metal to metal contact. These small metal particles can cause significant damage to the rest of the system. 

If you have a damaged engine (for any reason) the team at Sutherland Automotive will be more than happy to help you.

Contact us today!