The 2013 Hyundai Sonata Hybrid is the third year for the carmaker's first hybrid-electric vehicle.

And Hyundai's made some minor updates to the mid-size hybrid sedan that competes head-to-head with the Toyota Camry Hybrid (which pioneered the segment), the Ford Fusion Hybrid, and later this year the 2014 Honda Accord Hybrid as well.

For the new model year, the peak output of the Sonata Hybrid's electric motor has risen from 30 to 35 kilowatts (40 to 47 horsepower).

The motor is sandwiched between an updated version of Hyundai's 2.4-liter four-cylinder engine, optimized to run on the fuel-efficient Atkinson Cycle, and its six-speed automatic transmission, which has been modified to work even when the engine is off.

Total power output from the combined engine-motor combination is now 199 horsepower.

The 1.4-kilowatt-hour lithium-polymer battery pack also has a higher power output, from 34 to 47 kW, for better electric assist under high loads. It's both lighter and smaller, boosting trunk volume

The Sonata Hybrid has a number of aerodynamic changes to cut its drag coefficient to a claimed 0.24, one of the lowest for any production vehicle sold in the U.S.

The net result of these changes, along with refinement to the control software, is slightly higher EPA gas-mileage ratings: a 38-mpg combined rating (up from 36 mpg).

That's far lower than the EPA rating of 47 mpg combined for the Ford Fusion Hybrid, but owners of that car largely report real-world results of 36 to 40 mpg.

The original Sonata Hybrid, unfortunately, was one of the 2011 and 2012 vehicles whose EPA ratings had to be revised downward after Hyundai disclosed what it called errors in its testing procedures.

Between Hyundai and its sister company Kia, roughly a dozen different vehicles had their ratings lowered--meaning there's no more chest-pounding from Hyundai about the number of 40-mpg-plus vehicles it sells.

While Hyundai doesn't break out sales of the Sonata Hybrid in its monthly sales reports (unlike Ford, for instance), John Krafcik, CEO of Hyundai U.S., told Ward's Auto that the company sold 18,030 Sonata Hybrids during 2012.

That's roughly the number of Prius hybrids that Toyota sells each month.

The 2012 total, Krafcik said, was a 74-percent improvement over the 2011 total--which would put that year's Sonata Hybrid sales at about 10,400 cars.

Including mandatory delivery charges, the 2013 Hyundai Sonata Hybrid starts at $26,445 ($200 less than the comparable 2012 model) and the Sonata Hybrid Limited starts at $30,345.

We'll be driving a new 2013 Hyundai Sonata Hybrid on Wednesday, so tell us what you'd like to know about Hyundai's revised hybrid sedan.

Leave us your questions and thoughts in the Comments below.


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