Why my fuel choice is important

Posted by Super User | Tech Blog | September 24, 2023
Why my fuel choice is important

The demands of modern engines and the development of ethanol fuels has made things a little confusing for people as to what you should be putting in at the bowser. But it really is quite simple and can be one of the simplest decisions you can make to look

What are my choices?

So when you pull up at the bowser there are a variety of fuels you can choose. But which is the right one for your car. It is as simple as looking at the fuel cap. Most new vehicles will state what fuel they recommend for your vehicle as a MINIMUM. If your manufacturer states minimum is 95 premium unleaded, then it is as simple as you can only use Unleaded 95 or Unleaded 98. So it is NOT recommended you put regular unleaded, unleaded 91 in your vehicle or ethanol-based fuels.

What are the differences between fuels?

Here is a brief explanation of the major fuels that are available


This is a fuel based on ethanol. Ethanol is produced through the fermentation of vegetable matter. E85 contains 85% ethanol and produces less energy than petrol which means you will consume more fuel to cover the same amount of distance on petroleum-based fuel.

Regular Unleaded

Contains 91 octanes and should only be used for vehicles which recommend this.

Unleaded 95

Is a higher octane fuel and is required as a standard for most performance or late-model vehicles. Has the potential with it’s higher energy content to reduce consumption.

Premium Unleaded 98

Highest octane content available in petrol. Again, due to higher energy content, has the potential to reduce fuel consumption. Maximises the performance of your engine.

Now there are also some blends of fuels in 91 and 95 with ethanol. So this is something to be mindful if your vehicle does not recommend using an ethanol-based fuel in your vehicle.

Does it really matter if I put a cheaper fuel in my vehicle to save money?

I am sure we have all thought on at least one occasion with the price of fuel, it won’t hurt once or twice to put a cheaper fuel in my car. But it can. Putting the right fuel in your car is just as important as putting the right oil. Manufacturers don’t recommend a particular rating of fuel for no reason. The impact it can have on your engine for saving a few cents on each litre can cost you more money in the long run. Here in Australia, we particularly have a low-grade quality of petrol. Deposits formed from petrol/diesel can cause rough idling, poor acceleration and hesitation problems. Our sulphur content in petrol is as bad as some parts of Africa, South America. Even most of Asia has better petrol than in Australia. 95 and 98 fuels are cleaner fuels and have a lower sulphur content. So putting those cheaper fuels rather than the recommended 95 or 98 can mean less fuel efficiency and higher sulphur content causing possible clogging in your engine. Sulphur can clog the intake in your vehicle which means poor performance and can lessen the life of moving parts. If this happens, use Liqui Moly Petrol or Diesel Intake Cleaner to solve the problem.

It can be even worse if you are using E85 or ethanol-based fuel in your car that it is not recommended for. Because Ethanol is like alcohol it can grab and hold onto water more than what fuel can do. This water can then go through your engine, causing rust to form in parts of your engine. This rust can then flake travel along the engine causing damage to pistons, rings, seals or even just clogging up your filters. These are a much more expensive thing to fix or replace compared to those few cents saving when you put it in. And remember, every 5,000 to 10,000 km put in a fuel system conditioner/cleaner or petrol injector cleaner or diesel system cleaner to remove any harmful deposits that have built up and have your vehicle’s fuel system running to the best of its ability.

Putting the right fuel in that is recommended for your vehicle makes a huge difference in your fuel economy, better performance has your engine running like the manufacturer intended and saves you money in the long term on repairs. Remember, a few cents at the bowser can cost you a lot more down the track.

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