The 2012 Hyundai Sonata Hybrid doesn’t anymore have a rating of 40 mpg on the EPA test cycle but with the updates to the 2013 Hyundai Sonata Hybrid, it can now achieve 40 mpg on the highway. Hyundai still considers this hybrid as its most fuel-efficient model but it was one of several models involved in the recent MPG inflation controversy.
But with the introduction of the 2012 model, Hyundai says goodbye to its problems. The updated model is priced lower and has better fuel economy. Hyundai concentrated its efforts on three major hybrid system components: the lithium-polymer battery pack, electric motor, and hybrid starter generator. The most significant change is the battery pack. It has an output of 47 kW, an improvement over the 34 kW last year.
The pack offers more energy but it’s lighter and more compact. The battery has a weight of 87.8 pounds (a drop from 92.4) while trunk space has increased from 10.7 cubic feet to 12.1.
The extra battery capacity enabled Hyundai to boost the output of the electric motor without compromising its range or fuel economy. The motor is capable of delivering 35 kW (compared to last year’s 30 kW). Meanwhile, the hybrid starter generator (which starts the engine and synchronizes its speed to the transmission) can now deliver 10.5 kW of power, up from 8.5 kW.
As a result, Hyundai comes with smoother engine starts and extra time used in EV mode. The Sonata Hybrid is capable of reaching a speed of up to 75 mph using just the transmission-mounted electric motor. The six-speed automatic transmission and the gas engine – a variant of the Sonata’s 2.4-liter I-4 that runs on the Atkinson cycle – have been modified to make them a bit more efficient.
The Sonata Hybrid is now the only Hyundai to reach the momentous 4-0 highway number. According to EPA’s estimates, this model can return 36 mpg in the city and 40 on the highway. When combined, the base Sonata Hybrids can achieve 38 mpg while top-trim Limited models have a 37 mpg rating.