E20 petrol shift leaves Bengaluru motorists worried over mileage, repairs

While the Union government’s clean-energy mandate aims to reduce oil import bills and curb carbon emissions, its immediate impact on the ground has left daily commuters grappling with unexpected mechanical breakdowns, low fuel efficiency, and escalating repair bills. | Photo Credit: File photo The nationwide transition to E20 petrol, a fuel blend containing 20% ethanol and 80% fossil fuel, has triggered widespread anxiety among vehicle owners and mechanical repair workshops across Bengaluru.While the Union government’s clean-energy mandate aims to reduce oil import bills and curb carbon emissions, its immediate impact on the ground has left daily commuters grappling with unexpected mechanical breakdowns, low fuel efficiency, and escalating repair bills. For thousands of motorists navigating the city’s dense traffic daily, the shift has been anything but smooth. Owners of two-wheelers and older passenger cars have reported a sharp decline in vehicle performance.Mileage dropThe primary grievances remain a noticeable drop in overall mileage alongside chronic engine sputtering. “Ever since local fuel stations transitioned fully to the new blend, my scooter’s mileage has dropped by nearly five kilometres per litre,” said K. Vinay, a delivery executive based in J.P. Nagar.“What is worse than the poor fuel economy is the erratic engine behaviour. The vehicle jerks violently at traffic signals and often stalls out of nowhere. I had to get my fuel tank completely drained last week because of moisture accumulation, which cost me a chunk of my weekly earnings,” he added.Rush at mechanic shopsThe issue has led to an influx of distressed vehicle owners at local mechanical garages. Mechanics note that the distinct chemical properties of high-concentration ethanol are wreaking havoc on internal engine components, particularly in vehicles manufactured before April 2023 that lack material compatibility for biofuel blends.“We are seeing many complaints related to clogged fuel injectors, ruptured rubber gaskets, and heavily corroded fuel lines,” said M. Anthony, a senior mechanic running a multi-brand garage on Bannerghatta Road.“Ethanol aggressively absorbs water from the humid air. In a city like Bengaluru, which experiences frequent weather shifts, this water-ethanol mixture separates and settles at the bottom of the tank as a thick, corrosive sludge. Drivers mistake it for adulterated petrol, but it is actually the direct result of chemical phase separation inside their own vehicles,” he added.Transport expert M. N. Srihari stressed that the concerns of vehicle users should be given priority. He said that there was no need for an urgent approach to implementing E20 and that the government should have taken more time to consult all stakeholders, explain its advantages and disadvantages, and build public confidence.According to him, consumers are capable of adapting to changes in fuel prices or other adjustments, but gaining acceptance for a new system requires transparency and confidence. “E20 could have certain advantages, including ethanol’s longer shelf life and lower hazard compared with petrol in some emergencies. However, the impact on fuel economy, cost and vehicle users also needs to be considered,” he said. Published - September 02, 2026 06:01 am IST