New Delhi: The Centre has told Parliament that no scientific study has confirmed claims that E20 petrol causes engine damage or major vehicle problems. The government has told Parliament that concerns over E20 petrol damaging vehicle engines or reducing mileage have not been supported by scientific evidence. Mileage concerns remain a major debateWhile the government has rejected claims of engine damage, it has previously acknowledged that ethanol blending can affect fuel efficiency. The Centre has said E20 petrol may result in around 3-5 per cent lower mileage compared with conventional petrol because ethanol has lower energy content than petrol. It cited inputs from automobile industry bodies and said there have been no verified reports of large-scale engine failures caused by E20 petrol.