Indian Institute of Technology Kanpur (IIT Kanpur) has reported that E20 petrol has no notable impact on fuel efficiency in both recent and older vehicles, dismissing social media claims that the blend causes engine damage. The study by the institute’s Engine Research Laboratory found that observed reductions in mileage were minor and did not amount to technical harm to engines. The researchers advised motorists to consult vehicle manufacturer manuals and official guidelines rather than unverified online posts. Dhruv Raj Karana, a project scientist in the department of mechanical engineering, reported that the decrease in fuel efficiency with E20 was less than five per cent and suggested that such differences could arise from factors other than fuel. He indicated that back to back tests using pure petrol yielded comparable variations, and that extensive laboratory evaluation showed no evidence of corrosion or other technical problems attributable to the blend. The laboratory work was led by Professor Avinash Kumar Agarwal. The Ministry of Petroleum and Natural Gas had earlier acknowledged that E20 may reduce mileage by up to five per cent in some vehicles while emphasising that the environmental and lifecycle benefits offset the modest loss in efficiency. The institute’s findings align broadly with that guidance and seek to place observed performance changes in operational context rather than ascribe them solely to fuel composition. Motorists were urged to follow manufacturer recommendations and ministry advisories when choosing fuels. The research team also conducted trials with E85, a blend containing 85 per cent ethanol, and noted that such high concentration fuels require specially designed engines and compatible fuel systems. The institute characterised social media reports of widespread engine failure as scientifically unfounded and called for standardised testing protocols to address consumer concerns. Officials indicated that careful diagnostics and adherence to service guidelines would help distinguish genuine mechanical faults from normal variation in test outcomes.