Ethanol is a colourless liquid (alcohol) which is produced by fermentation of sugars and carbohydrate polymers and is generally manufactured from grain or sugar. Blending of ethanol in petrol has been suggested as a means of reducing greenhouse gas emissions and alleviating adverse economic conditions in the Australian sugar industry.

The Australian Federal Government is currently legislating that ethanol can be added to petrol in blends of up to a maximum of 10%. This is called E10. Legislation states that this must be labelled on the petrol station pumps which dispense E10, so that the consumer will have a choice whether or not to purchase ethanol blended fuels.

Mazda Corporation of Japan has supplied a list of vehicles which can operate on ethanol blends of up to 10% (E10). These vehicles are listed in the table below. Mazda Corporation has advised that vehicles which are not listed in the table ARE NOT SUITABLE for use with ethanol blended fuels.

• There is an increased possibility for the metal fuel tanks and lines to corrode or rust.
• There is an increased possibility for plastic fuel tanks to swell and break down.
• There is a possibility for plastic and rubber fuel lines to deteriorate.
• There is a possibility for fuel injector o-rings to break down.
• Carburettor floats and seals are susceptible to deterioration.
• Certain engine components may not be compatible.
• Engine management mapping parameters may not be entirely compatible with E10, thereby creating idle and driveability concerns, starting concerns and hot weather performance issues.

• Ethanol is an oxygenated fuel. E10 (which is oxygenated gasoline) may reduce fuel economy by an average of 2 – 3% because oxygenates contain less energy than non-oxygenated petrol. As such, there may be fewer kilometres per tank of fuel when using E10.
• Ethanol has a high affinity for water. Therefore, ingress of water could result in ethanol blends of petrol to break down into separate water/ethanol and petrol layers. This could create driveability concerns as there is the possibility of water/ethanol slugs reaching the engine.
• In some older vehicles, deposits in fuel systems can be loosened by E10 which may cause fuel filters to become blocked.
• Coarse ethanol, which is of poor quality (like ordinary fuels of poor quality), may cause poor idle, derivability concerns and starting issues, even if the vehicle is suitable to operate on E10.