Why your car might perform better on premium fuel

Where Can I Find the VIN (Vehicle Identification Number)?

The vehicle identification number (VIN) is composed of 17 characters (digits and capital letters) that act as a unique identifier for the vehicle. A VIN displays the car's unique features, specifications and manufacturer.

The VIN can be found in a couple of places including on the car's registration label (1), on the compliance plate in the engine bay (2) or on the passenger side windshield (3), or on one of the door posts (where the door latches when it is closed) (4). See the image below:

Look for the VIN in these other locations:

  • Insurance card/Insurance policy
  • Vehicle title and registration certificate


When you go to the fuel station, do you understand why there are so many different options to choose between? We don't just mean petrol and diesel - what about the numbers on the fuel types? When you save money on buying a used car, having had it checked out with a CarHistory report first, you don't want to ruin the engine by using the wrong sort of fuel!

You should take your time considering which fuel is best for your car.

If you don't know what fuel you should be using, you may not be doing your car any favours. Some engines run better on more refined fuel, and some aren't tuned to use 98-octane petroleum1. Some time ago, you could only choose between standard petrol and diesel. The number of options now (and the difference in price) means you should take your time considering which fuel is best for your car.

What do the octane numbers mean?

When pumping standard petroleum, you will often see three numbers to choose between - 91, 95 and 982. The higher the number, the higher the octane level in the fuel, which means the combustion rate is more controlled inside the engine1. You may never have used anything other than standard unleaded fuel (91), so you won't know the difference that using premium (95) makes.

Give it a go the next time you're at the pump. If your car states on the fuel cap that you should never use anything below 95-octane petroleum, then you could be doing serious damage to your engine by pumping standard unleaded1. That being said, if you prefer to use a higher octane fuel (98) and don't mind paying a little extra for the better performance and efficiency, then you can go up in octane from what the manufacturer recommends 1.

There are now premium diesel options on the market as well, which offer the same sort of performance and efficiency increases that premium petroleum does1. Most diesel cars do not require you to only use premium, but it could allow you to drive further on a single tank, or keep your engine in better condition over time1.

You know where the fuel comes from, but do you know what happens to it before it gets pumped into your car?


Why could using standard fuel hurt your car?

Pumping standard fuel into your car means that there are more uncontrolled combustions inside the engine, which can wear your engine out faster1. Due to the nature of fuel and motor engines, combustion is what drives the car, however the block only needs a certain amount of combustion from the fuel to work efficiently. Any more and it can be damaged - which is why using standard fuel is not always a good idea (even as a cost-saving measure).



Over time, using standard fuels could mean that your engine breaks down more regularly, and you'll have to pay a lot more to get it fixed. In older cars, the difference between using standard and premium fuels is almost negligible, but in newer cars, and especially in European cars, using anything less than 95-octane is not advised1. If you don't drive something from before the year 2000, you shouldn't risk using 91-octane fuel.

Diesel engines, on the other hand, are all designed to be powered by standard fuel. They are manufactured far more sturdily than petrol engines, so can take more wear and tear before needing serious maintenance1. Using the cheaper standard diesel is acceptable and can help you to save money, but if you want a little more bang for your buck, and think your engine deserves a treat every now and then, fill up with premium diesel.

The differences between standard and premium fuels are not all that noticeable to us, but to the cars, they mean a lot. Take that into consideration the next time you're at the pump. For more information about buying a used car, make sure you get in touch with CarHistory today.

1. Comparethemarket. The best fuel for your car. Accessed February 2017.

2. Business Insider. Here's The Real Difference Between Premium And Regular Gas. Accessed February 2017.

View a sample report >