You may have heard that the fuel we use in our vehicles is changing as part of broader efforts to reduce environmental impact. One of the most significant changes involves the shift from E5 to E10 petrol.
What is E10 Fuel?
Most super unleaded petrol currently sold is rated E5, meaning it contains 5% ethanol and 95% petrol. The ethanol is produced from renewable sources, so increasing its share in fuel helps reduce our reliance on fossil fuels and cuts carbon emissions—an essential step in tackling climate change.
The transition to E10 (10% ethanol) has been in the works for some time, and most petrol-powered cars manufactured from 2011 onwards are compatible with it. If you’re unsure about your car, you can check compatibility online, consult your vehicle’s manual, or check the label inside your fuel cap.
It’s worth noting that older and classic vehicles, including many motorcycles and pre-2011 cars, may not be compatible with E10. Thankfully, E5 super unleaded (97+ octane) will continue to be available for the foreseeable future to support those engines.
How Will E10 Impact My Car?
Switching to E10 may slightly affect fuel economy—lab tests suggest a reduction of around 1%. That’s because ethanol has less energy per litre than pure petrol.
There are also some mechanical considerations:
- Ethanol is hygroscopic, meaning it absorbs water. This can lead to internal corrosion in the engine and fuel system.
- Ethanol is harsher on rubber components, such as hoses and seals, which can degrade faster due to the alcohol content. In some cases, this may cause leaks or even failure in fuel lines.
As a general rule, cars with carburettors should not use E10.
How Can I Protect My Porsche?
For older Porsches—particularly those built before 2011—the primary concern is the impact of ethanol on rubber components within the fuel system. This includes the filler hose, fuel lines, and seals. As these degrade, they can cause leaks or allow rubber fragments to enter the engine.
Fortunately, specialist suppliers are offering upgraded, ethanol-resistant components designed for classic vehicles. At RPM Technik, we’re collaborating with one such supplier to provide a reliable and cost-effective upgrade for older Porsches. These upgraded fuel lines help ensure long-term compatibility with higher ethanol content fuels—effectively future-proofing your car.
If your Porsche was built in 2011 or later, you’re in luck. These models were designed to handle higher ethanol blends, such as E10, from the outset.
Looking Ahead
Fuel standards and compositions will likely continue evolving in the coming years. We’ll be monitoring these changes closely and will keep you updated on how they may affect Porsche models, both old and new.
If you have any concerns about how E10 fuel could impact your Porsche, don’t hesitate to get in touch. We’re here to help you keep your car running at its best—whatever the fuel pump may bring.
