What Gas Does an Audi A3 Use? (Can It Use Regular Gas?)

If you’ve recently bought an Audi A3, you may wonder which type of gas you should choose at the pump.

Can the Audi A3 use regular gasoline, or does it need premium?

The Audi A3 can use regular (87 octane), mid-grade (89 octane), or premium (91/93 octane) gas. The Audi A3 will run fine on regular gas, but Audi recommends using premium gas for increased resistance against knocking.

Read on for more information about the type of fuel your Audi A3 can take!

At a Glance: What Gas Can an Audi A3 Use?

Are you standing at a fuel pump and wondering what to put in your Audi A3?

If so, here is what you should know:

Using regular gas for the Audi A3 is fine. However, if you can, try to use premium gas for better mileage and lower long-term maintenance costs.

Here is what you can and cannot put in the gas tank of your Audi A3:

Category	Type	Is It OK?	Notes
Gas	Regular (87 octane)	✓	Minimum required octane level by Audi, the car will run safely.
Gas	Mid-grade (89 octane)	✓
Gas	Premium (91 octane)	✓	Recommended octane level by Audi, the engine will be more resistant to knocking.
Gas	Premium (93 octane)	✓
Gas	Ethanol-based (E10)	✓	Same as the typical gas at most pumps.
Gas	Ethanol-based (E15)	!	Not optimal for the car, but it won’t be a danger in the short term. It can only be used for Audi A3s from 2001 or newer.
Gas	Ethanol-based (E85)	!	Mostly not OK. It can only be used if your A3 has a flex-fuel system.
Gas	Reformulated Gasoline (RFG)	✓	A type of gas that burns more cleanly, about 30% of the gas sold in the US is RFG. (Source)
Additives	Fuel injector cleaner	!	Be careful; it can potentially damage the engine when overused.
Additives	Octane booster	!	Be careful; it can damage the engine when misused.
Additives	Fuel stabilizer	!	Be careful; it can damage the engine when misused.

Does an Audi A3 use regular or premium gas?

So, let’s dive a bit more into whether you should use regular or premium gas for your Audi A3.

Officially, if you check the manual of an Audi A3, Audi says that regular gas has the minimum required octane level, while premium gas is recommended.

The key here is the difference between the word ‘required’ and ‘recommended.’

The minimum required fuel quality for the Audi A3 is regular gas (87 octane). You may risk damaging the fuel system or engine with any lower-octane fuel. However, in any case, using regular gas is safe for the Audi A3.

However, Audi also makes a recommendation:

It is recommended to use premium gas for your Audi A3. It will positively impact your fuel economy, engine performance, and long-term maintenance costs.

If you have a performance-oriented version of the Audi A3, like an A3 e-Tron, A3 or S3 with the turbocharged 2.0-liter petrol engine, or even an RS3, it is even more important to use premium gas.

These engines have high compression ratios and use direct injection technology.

Because of this design, the fuel is more likely to ignite before it should, causing a phenomenon called knocking.

Premium gas has a higher octane rating, which reduces the likelihood of early combustion (knocking). Therefore, it’s highly recommended for these performance-oriented engines!

Also, if you’re putting your Audi A3 under heavier loads, like when towing a trailer or caravan, it’s better to use premium gas instead of regular gas.

What is the difference between regular and premium gas?

Regular (87 octane), mid-grade (89 octane), and premium (93 octane) gas at a pump

Regular gas has an octane rating of 87, while premium gas has an octane rating of 91 or 93.

The higher the octane rating, the lower the likelihood of gas igniting early in the engine’s cylinder. As mentioned, this is called knocking, which causes hitting/pinging sounds and a power reduction.

Commonly, it’s better to use premium gas for engines that are turbocharged or have a high compressions ratio. This will reduce the risk of knocking and improve fuel economy.

However, if premium gas is not recommended for your car, there is no reason to use it.

Can you use ethanol-based fuels for the Audi A3?

Ethanol-based fuels are fuels that contain ethanol, which is a renewable fuel made from biomass. Biomass consists of a variety of plant materials.

It looks something like this:

Corn put into the gas tank filler cap of a car

That’s a joke, of course!

In reality, over 98% of gasoline in the US contains ethanol. The most common ethanol-based fuel is E10, which consists of 10% ethanol and 90% gasoline.

Ethanol-based fuels reduce air pollution, but at the same time, using gas that contains a high concentration of ethanol can damage your vehicle.

E10 is a standard that’s commonly accepted to be safe for most cars on the road today, including the Audi A3.

However, you may occasionally find E15 gas containing 15% ethanol and 85% gasoline. In the US, E15 can be found in 30 states at over 2,400 pumps (source).

E15 is not optimal for the Audi A3, but it won’t be a danger in the short term. However, it can only be used for Audi A3s from 2001 or newer.

Once you increase the ethanol percentage further, it really won’t be too good for your car.

For instance, E85 is also available in some places, but it can only be used for your Audi A3 if you have a flex-fuel kit.

FAQs about gas for the Audi A3

If you have any more questions about which gas to use for your Audi A3, take a look at these FAQs:

What happens if I put regular gas in my Audi A3?

Nothing will happen if you put regular gas in your Audi A3. The Audi A3 is designed to run safely on regular gas. However, if you can, it is advisable to use premium gas.

Can I use additives for the Audi A3?

You can use additives for the Audi A3. However, it is important to carefully read the manual beforehand and avoid using additives too frequently, as this can damage the engine or fuel system.