The Tata Sierra is available with a naturally aspirated 1.5-litre petrol, a 1.5-litre diesel, and an all-new in-house developed 1.5-litre turbo-petrol (Hyperion) engine. Manual and automatic gearbox options are offered with the petrol and diesel, while the turbo-petrol is available only with a 6-speed automatic.
We’ve already detailed our driving impressions of this direct-injection 1.5-litre turbo-petrol, and compared it with the Hyundai Creta. Here, the focus is on its real-world fuel efficiency.
- Doesn’t get an auto engine stop-start function
- 2 drive modes - City and Sport
- Weighs 1,552 kilos
Tata Sierra turbo-petrol AT real-world mileage test
Sierra turbo-petrol AT has an average fuel efficiency of 10.10kpl
The Sierra’s 1.5-litre direct-injection turbo-petrol produces 160hp and 255Nm, and is paired with a 6-speed torque converter. Tata has provided City and Sport drive modes, but there’s no Eco mode, nor does it get an automatic engine stop-start function to help curb fuel consumption while idling. Also worth noting is its kerb weight: in top-spec guise, it tips the scales at 1,552kg, making it 183kg heavier than a fully loaded Creta N Line.
In our tests, the Sierra turbo-automatic delivered 6.49kpl in the city and 13.70kpl on the highway. To double-check, we repeated the tests, and it returned similar figures. Its substantial weight, strong and immediate responses, and the absence of fuel-saving measures likely contribute to the low city efficiency.
Interestingly, its highway efficiency isn’t too far off the diesel-automatic’s figure. Contributing to its relatively more respectable efficiency could be limited stop-go scenarios, as well as a tall sixth gear, similar to the diesel’s, which ensures the turbo-petrol spins at a relaxed ~1750rpm while cruising at 100kph.
Autocar India’s fuel efficiency testing
Before our real-world fuel efficiency tests, we fill our test cars’ tanks to the brim and maintain tyre pressures based on the manufacturer’s recommendation. These cars are driven in fixed city and highway loops in and around Navi Mumbai, and we maintain certain average speeds. Throughout the tests, we run the aircon at 22-degrees in full-auto mode, and other electricals, such as the audio system, indicators and wipers, when required, just like a regular user would. Periodic driver swaps further neutralise variations in driver patterns. At the end of each cycle, we calculate efficiency by filling the tanks to full again.
Uday Singh
Saptarshi Mondal
Viraaj Bhatnagar
Rivan RS 
Dipan Sur
