“Business is brisk,” says 53-year-old Abdul Aziz, a mechanic and co-owner of a repair shop in Karol Bagh’s Nala market, New Delhi, a bustling car repair bazaar. He says this flashing a wry smile, his mouth stained red by paan. The surge in business, he says, is being driven by a growing number of owners arriving with strikingly similar complaints. Over the past few months, motorists have been reporting a sharp drop in fuel efficiency and vehicles that jerk while driving. Mechanics call it “gaadi missing de rahi hai” — a symptom that often points to poor fuel delivery. According to Aziz and his business partner, Tanveer Ahmed Khan, the most common causes are clogged fuel injectors and blocked fuel filters.The Nala market, as the busy automobile hub is locally known, is home to nearly 100 repair shops lined up in two parallel rows beneath a sprawling canopy of old trees. Signboards advertising engines, tyres, and spare parts hang overhead. Even in a steady drizzle, bonnets remain propped open as mechanics slide beneath dashboards and around engine bays to reach inaccessible corners. Worn tools, grease-stained hands, and decades of experience keep both the vehicles and the market humming.Khan says mechanics are also noticing unusually heavy carbon deposits in fuel injectors, and carburettors of older vehicles, along with a rise in oxygen (O2) sensor failures. “Almost every car that comes in now has to be opened up for inspection,” he says.According to the mechanics, these complaints are a relatively recent phenomenon that coincides with the nationwide rollout of petrol blended with 20% ethanol (E20) as the default fuel at retail outlets since April 2025, 5 years ahead of the original timeline under the Ethanol Blended Programme. The programme seeks to improve India’s energy security by reducing dependence on imported fossil fuels, support farmers by creating a market for ethanol feedstock, and lower vehicular emissions.