Why India's petrol shift has motorists fuming

India’s aggressive drive to expand ethanol-blended petrol is facing growing resistance, with a protest march on Tuesday demanding the government rethink its decision to make E20 fuel the national standard. Opposition leader Arvind Kejriwal marched towards Prime Minister Narendra Modi’s residence carrying petitions signed by more than 200,000 people, but was stopped by police before reaching his destination. India, the world’s third-largest auto market, says the biofuel move is helping curb dependence on imported crude and boost farm incomes. But motorists have voiced concerns over vehicle performance, and the government’s campaign has upset India’s vast middle class — a key voter base for…