A study commissioned by the Centre has found that some rubber parts and gaskets in BS-III vehicles may need to be replaced when using E20 fuel. The Union government informed Parliament about the study’s findings on Tuesday, July 28, 2026. The study was carried out by Indian Oil Corporation Limited, Indian Institute of Petroleum, Society of Indian Automobile Manufacturers, and Automotive Research Association of India.
According to Union Road Minister Nitin Gadkari, the study found that some rubber parts and gaskets in BS-III vehicles introduced from April 1, 2005, and manufactured prior to 2016 may require replacement. However, this can be easily managed during routine servicing of the vehicle. The findings of the study have not been made public. Minister Gadkari was responding to a question from CPI MP A.A. Rahim on the impact of E20 on vehicle performance, fuel efficiency, engine durability, and maintenance costs.
The study found that there is no need to modify car and two-wheeler engines, other than those in BS-III vehicles. The Minister stated that the studies confirmed that even legacy vehicles did not exhibit any significant variations in performance, nor did they show abnormal wear-and-tear when operated with E20 fuel. The study also found no issues related to drivability, startability, metal compatibility, or plastic compatibility.
However, there have been widespread anecdotal complaints of vehicles misfiring or breaking down, with some users attributing the problems to E20 fuel or contaminated E20. On concerns about fuel efficiency, Minister Gadkari said that vehicle mileage is influenced by a host of factors beyond just fuel type, including driving habits, maintenance practices, tyre pressure and alignment, and air conditioning load.
