Nitin Gadkari's Controversial Take on Fuel Efficiency Amid E20 Petrol Debate

Union Minister Nitin Gadkari has stirred controversy with his remarks on fuel efficiency, asserting that ordinary car owners cannot accurately measure their vehicle's mileage. This statement comes amid the government's push for E20 petrol, which has faced criticism for potentially reducing fuel economy. Gadkari emphasizes the need for authorized dealer testing equipment to obtain accurate readings. As vehicle owners express concerns over decreased mileage, the government acknowledges the possibility of a 3-5% reduction in fuel efficiency with E20. This article delves into Gadkari's claims, the government's stance, and the implications for car owners and the automotive industry.

By Narendra Chaudhary Jul 14, 2026, 09:58 IST

Gadkari's Surprising Statement on Fuel Efficiency

In the midst of ongoing discussions about ethanol-blended (E20) petrol in India, a striking statement has emerged from Nitin Gadkari, the Union Minister for Road Transport and Highways. He asserted that ordinary car owners cannot accurately gauge their vehicle's fuel efficiency (mileage). Gadkari emphasized that drivers should rely solely on testing equipment provided by authorized dealers.

During an interview with a news channel on Monday, Gadkari responded to a journalist's claim regarding a significant drop in mileage after the government's mandatory switch to E20 petrol. The journalist reported that their car's mileage had plummeted from 11 km/l to 7 km/l after purchasing a vehicle in 2023, which is likely compatible with E20.

In response, Gadkari questioned how the journalist arrived at that figure, referencing the mileage display on the dashboard. He stated, "I checked it in my car, just like everyone else does." He reiterated that accurate readings of fuel efficiency can only be obtained through manufacturer-authorized testing equipment.

Government's Acknowledgment of E20 Petrol's Impact

This conversation took place shortly after the central government acknowledged that E20 petrol could reduce fuel economy by 3-5% in certain vehicles, although they defended their fuel policy. Last week, the Ministry of Petroleum and Natural Gas released a Q&A document addressing criticisms of the ethanol-blended petrol program. The government admitted that E20 petrol might lower fuel efficiency in some cars but argued that mileage is not the only metric to consider.

The ministry stated, "It is true that fuel economy may decrease by 3-5% in some vehicles. However, mileage is just one measure." The government mandated the sale of E20 petrol nationwide starting April 1, aiming to increase ethanol blending, reduce reliance on imported crude oil, and cut emissions.

Concerns from Vehicle Owners and the Automotive Industry

Despite the government's efforts, the initiative has faced backlash from vehicle owners and raised concerns within certain sectors of the automotive industry. Car owners have reported decreased mileage, and some manufacturers have questioned the performance of blended fuel in older vehicles.

Can Drivers Accurately Check Mileage at Home?

Not entirely. However, they can get a reasonably accurate estimate. Modern cars calculate fuel economy using data from the fuel injected into the engine, the distance traveled, and inputs from the Engine Control Unit (ECU). While dashboard readings are merely estimates, they often fall within a 2-5% range compared to manual calculations based on a full tank.

Automotive experts generally consider the full-tank method to be the most accurate real-world test. Drivers fill the tank, reset the trip meter, drive normally until the next refueling, and then divide the distance traveled by the amount of fuel added (in liters).

What Does the Dealer's Machine Measure?

The manufacturer's diagnostic tool does much more than just display fuel economy. It reads detailed data from the ECU and checks whether components like fuel injectors, oxygen sensors, and airflow sensors are functioning correctly. It can also detect engine malfunctions and verify ECU calibration, which can impact fuel consumption.

However, it does not directly measure real-world mileage under all driving conditions. Factors such as traffic, city versus highway driving, air conditioning use, tire pressure, driving style, and vehicle load also affect fuel economy.

Evaluating Gadkari's Claim

In reality, a car's onboard display provides a rough estimate, while the full-tank method offers a more accurate measure of real-world fuel economy. The dealer's diagnostic equipment is primarily used to identify mechanical or electronic issues affecting fuel efficiency, rather than serving as the sole method for determining mileage.