'E20 petrol may cut mileage by up to 5%, but doesn't damage engines': Govt tells Parliament

In a written reply in the Rajya Sabha, Minister of State for Petroleum and Natural Gas Suresh Gopi said fuel economy is influenced by several factors, including driving style, vehicle maintenance, tyre pressure, wheel alignment and the use of air conditioning. The government said the drop in mileage for some older vehicles is generally limited to around 3 to 5 per cent.

source https://timesofindia.indiatimes.com/india/e20-petrol-cuts-mileage-by-up-to-5-in-older-vehicles-govt-tells-parliament/articleshow/132530985.cms