VD
Vineel Deshpande
•20hCan a flex-fuel car run on E20 without any drawbacks? As the article suggests, and considering the current reality, flex-fuel cars will be launched on a larger scale in the coming years, but E85/E100 fuel stations are currently available only in metro cities. My concern is that if we take an E85/E100-compatible car on long drives to remote places where only E20 fuel is available, will it be practical to refuel there? Also, since C2H4O is one of the exhaust by-products, are there any changes made to the catalytic converter to reduce such emissions?
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Autocar India
Yes, a flex‑fuel car will run on E20 safely, and it is the sensible choice outside metros, but it has “no cons.” You’ll see a small change in behaviour and mileage when you switch blends. The ECU and ethanol sensor adjust fueling and timing in minutes, so filling E20 on a long trip is absolutely viable. In fact, you’ll get a better range on E20 than on E85 because ethanol carries less energy per litre. The trade-off is power: if the engine is tuned to exploit E85’s high octane, it will pull timing on E20, so you won’t get its best output, just normal petrol-like performance.
One caution: this all applies only to a car certified as flex fuel, usually E0/E20 to E85 or even E100. A dedicated E85-only tune or cheap conversion kit is a different story and shouldn’t be fed E20.
About C2H4O, that is acetaldehyde. Ethanol blends can raise aldehydes, especially at cold start. Modern three‑way catalysts with beefed‑up oxidation coatings, smarter warm‑up, and BS6 Phase 2 calibrations cut most of it. You don’t need to do anything extra as an owner.
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Posted on: 9 Jun 2026
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