E10 compatibility – Which cars can tolerate E10?

The good news in advance: Most cars with gasoline engines can tolerate E10 fuel without any problems. This applies to most cars built from 2000 onwards and to practically all cars built from 2012 onwards. The so-called biofuel E10 will be launched on the German market in 2011. Since then, it has been available nationwide at petrol stations.

E10 gasoline: The most important things in brief

• Fuel for gasoline engines with max. 10% ethanol admixture
• Most cars with gasoline engines can tolerate E10
• Advantages: Costs, environment (CO2 balance)
• Disadvantages: additional consumption, agricultural land for fuel production

E10 – What kind of fuel is it?

E10 is a fuel for gasoline engines that is composed of "normal" super gasoline and up to ten percent ethanol blended. The "normal" Super E5 contains a maximum of five percent ethanol content. Therefore, the industry also refers to it as "E5". The technical term for ethanol is ethyl alcohol. The fuel is obtained from fermented sugar beets, sugar cane and grain. For this reason, E10 is considered a biofuel. In this context, "organic" means that the ethanol is obtained from material of biological origin, i.e. based on biomass.

In order to avoid misfuelling, E10 petrol pumps in 2011 must first be provided with a sticker that clearly reads "Super E10 sulphur-free". In addition, the following information must be clearly legible on the pumps: "Contains up to 10% bioethanol" and "Does your vehicle tolerate E10? Obtain manufacturer information! If in doubt, fill up with Super or Super Plus!" Since 2018, Germany has been obliged to label fuel types uniformly across the EU. For gasoline, round symbols with an E and an octane number indication in the middle are used. Accordingly, Super 95 and Super Plus 98 become E5, Super E10 becomes E10.

What are the advantages of E10?

The most obvious advantage of E10 over premium gasoline is the price. E10 costs an average of around five cents per litre less than Super. With an assumed mileage of 30,000 kilometers per year and a real consumption of eight liters per 100 kilometers, this difference corresponds to an annual saving of around 120 euros at a liter price of 1.40 euros for E10 and 1.45 euros for Super. However, E10 has an additional consumption of around 1.5 percent compared to Super due to its lower energy density. Therefore, the calculation does not quite add up, but there is still a cost saving.

The more significant advantage lies in the environmental compatibility of E10 compared to Super. The theory: Bioethanol, unlike mineral oil, is obtained from renewable raw materials and therefore the CO2 balance. The CO2 generated during driving is previously bound when the plant grows. CO2 savings compared to gasoline made from mineral oil with 1:1 replacement: 60 to 75 percent.

To prove this advantage, the Federal Association of the German Bioethanol Industry (BDBe) conducted a study with the help of the ADAC, in which five cars from different manufacturers were alternately refueled with E10 and Super. The result, according to BDBe: The widespread use of E10 could save around 3.1 million tons of CO2 emissions per year.

What are the disadvantages of E10?

The environmental benefits of E10 are often critically questioned. The better climate balance of E10 compared to Super seems indisputable when it comes to the mere consumption values on the road. However, the production of biofuel ties up agricultural land and withdraws it from food production. This, it is feared, will create competition for land as well as for food. If other natural areas (moors, forests) are opened up for agriculture as a result, the CO2 effect can be extremely negative, as such natural areas bind a particularly large amount of CO2. The Biofuel Sustainability Ordinance therefore prescribes a greenhouse gas reduction of at least 60 percent. Otherwise, biofuel may not be sold in the EU.

How harmful is E10 really?

In addition to the lower calorific value and thus slightly higher consumption, E10 gasoline has another technical disadvantage. In combination with high pressure, ethanol promotes the reactivity of certain materials: aluminium can corrode. However, this scenario only applies to direct-injection engines that operate at high fuel pressure due to their design. Early variants are not designed to run on ethanol and are therefore at risk.

According to studies by the ADAC, corrosion can occur in extreme cases even after a single refuelling. However, a single refueling with E10 usually does not lead to engine damage. However, if sensitive engine parts come into contact with the fuel for a longer period of time and more often, leaks can occur, according to an ADAC long-term study. Leaking gasoline also poses a fire hazard. In addition, E10 can also damage seals and hoses.

Therefore, not all gasoline engines are approved for E10 by the respective car manufacturer. However, if a car is approved for E10, then E10 is not harmful to the engine. Another tip: The ADAC expressly warns against additives from the aftermarket that are supposed to make E10 compatible with every car. So stay away from these products! If a car with a gasoline engine that is not approved for E10 has been accidentally misfueled with E10: Don't panic. The tank does not have to be pumped empty. If you want to be on the safe side, you can empty the tank about half within a few days and refuel it with regular premium gasoline - this dilutes the ethanol content in the fuel.

E10 compatibility – Can my car tolerate E10?

Most cars with gasoline engines can fill up with E10 without any problems. First of all, this applies to almost all passenger cars that have been registered since the introduction of the fuel in 2011 – but also to most older models. In the USA, E10 has been the standard since 1972. Technically, the use of all gasoline engines with intake manifold injection or carburettors is considered harmless, but problems exist with models with direct injection that have bare aluminum parts in the high-pressure range. Most car manufacturers have approved the majority of their vehicles from the 2000 model year onwards for E10 across the board, some have also tested older models and named specific exceptions.

Many newer models, for which the manufacturer provides the fuel Super Plus (98 octane), are usually still approved for Super E10. Although the fuel has a low knock resistance of only 95 octane, fundamental problems are not to be expected. Mitsubishi points out that sports models such as the Lancer Evo can also be refueled with E10, but that performance and comfort losses are to be expected. BMW states that the prescribed octane number must be observed, especially for older models before 1990. The vehicle's operating instructions are decisive here.

Where can I find out if my car can tolerate E10?

Critical: Although manufacturers and importers approve a large number of cars for E10 across the board, some only test the compatibility up to a certain year of construction (often: 1997 or 2000). So it may be that old models are not officially allowed to fill up with E10, but technically would have no problem with it. Nevertheless, drivers who are unsure whether their car can tolerate E10 should obtain information about the E10 compatibility of their vehicle before refuelling for the first time. The first point of contact is the car manufacturer. If there is no information about E10 in the operating instructions, it is worth taking a look at the manufacturer's website. Some brands, such as Audi or Toyota, offer the option of retrieving E10 compatibility via the vehicle identification number (VIN). You can find them in the vehicle registration document as well as in various places in the vehicle itself, for example stamped into the sheet metal of the door frame.

In addition, Deutsche Automobil Treuhand GmbH (DAT) has compiled a list of all motor vehicles that can tolerate E10. The exceptions of the respective manufacturers are also listed there. For example, Volkswagen mentions three engines from the 2004-2005 model years in the VW Golf 5 that cannot tolerate E10. All subsequent TSI models of the Golf 6 and Golf 7 series are approved for Super E10 without restrictions. The list of DAT can be downloaded as a PDF. The E10 compatibility of your own car can also be found out directly at the petrol station. In addition, automobile clubs such as the ADAC or the Auto Club Europa (ACE) can help. If, despite all efforts, the E10 compatibility of the car cannot be ascertained, the ADAC categorically advises against refueling with E10.