India's nationwide shift to E20 petrol has sparked a debate among motorists over fuel efficiency, vehicle compatibility and long-term maintenance. E20 is petrol blended with 20% ethanol, a biofuel produced from agricultural feedstocks such as sugarcane, maize and surplus food grains. The government says the move will reduce crude oil imports, lower emissions and support farmers by creating demand for ethanol-producing crops. However, some vehicle owners, particularly those with older models, have questioned whether E20 could affect engine components or reduce fuel economy. The discussion has intensified following the rollout of E20 fuel across the country and speculation over the possibility of higher ethanol blends in the future. The Centre has rejected claims that E20 causes widespread engine damage, saying the fuel meets Bureau of Indian Standards (BIS) specifications and was introduced only after testing with automobile manufacturers. Several major automakers have also said they have not found evidence linking E20 to engine failures in serviced vehicles. While the government says E20 is safe for compatible vehicles, it has acknowledged that fuel economy may decline slightly compared with E10 petrol. Some automotive experts have also noted that older vehicles could experience higher wear on certain components over time, though they distinguish this from catastrophic engine failure. As India expands ethanol blending, the debate has highlighted the need for clearer consumer information on vehicle compatibility, mileage and maintenance.