E20 Petrol: Should You Worry? Know Its Impact On Mileage And Engine

The Indian government made E20 petrol, a fuel blend containing 20% ethanol, mandatory across the country in April 2025, aiming to reduce dependence on imported oil and promote cleaner energy. While this is a major step toward environmental sustainability, many vehicle owners are wondering whether E20 petrol could harm their cars or bikes. Let’s understand the facts in simple terms.

Can All Vehicles Run on E20 Petrol?

According to the Ministry of Road Transport and Highways, vehicles manufactured after April 2023 are designed to run safely on E20 petrol. These engines are compatible with a 20% ethanol blend and won’t face any performance issues.

However, vehicles made between 2012 and 2023 are mostly suitable for E10 fuel (which contains 10% ethanol). Using E20 in older vehicles, especially those made before 2012, could pose some risks to the engine and fuel system.

Does E20 Fuel Affect Mileage?

A survey by LocalCircles shows that vehicle owners, particularly those with cars or two-wheelers purchased before 2023, report higher fuel consumption in 2025, despite the government asserting that E20 petrol is safe for all vehicles.

Can E20 Petrol Damage the Engine?

E20 petrol does not cause immediate damage, but long-term effects may appear in older vehicles. Because ethanol attracts moisture and is mildly corrosive, it can:

• Gradually wear out rubber and plastic parts like fuel pipes and gaskets.
• Cause metal components to rust, especially if the vehicle remains unused for long periods.
• Lead to fuel separation issues, where petrol and absorbed water settle differently, affecting engine performance.

The LocalCircles survey also shows that 28% of owners of petrol vehicles (purchased in 2022 or prior) claimed that they are experiencing unusual levels of wear & tear or need for repair in 2025 with regards to engine, fuel line, tank, carburetor, etc.

In short, modern engines are built to handle ethanol blends safely, but older engines may face wear and corrosion over time.

Will It Affect Vehicle Warranty?

If your vehicle is not designed for E20 and you still use it, the manufacturer’s warranty could become void. Many automakers have clarified that any damage caused by higher ethanol content will not be covered under warranty.

How to Check If Your Vehicle Supports E20 Petrol

To find out, simply check your vehicle’s user manual — it clearly mentions the recommended fuel type. Generally:

• Vehicles manufactured after April 2023 are E20-compatible.
• Older models (before 2023) are usually limited to E10.

E20 petrol is a positive step for the environment, but vehicle owners must ensure compatibility before use. Using the right fuel blend ensures better mileage, engine health, and safety — without affecting warranty or performance.