January was a month of extremes for Orange County automakers, with some posting record sales and others seeing a plunge.

South Korea-based Hyundai Kia Automotive Group’s two automotive brands once again topped their monthly sales records for January.

Fountain Valley-based Hyundai Motor America Inc., with temporary headquarters in Costa Mesa, saw January sales up 15% from a year earlier, to 42,694 vehicles for the month.

Hyundai sister company, Irvine-based Kia Motors America Inc. reported sales up 27.8% last month from a year earlier to 35,517 vehicles.

Auto sales nationally began the year strong with sales up 11.4% to 913,287 vehicles, according to Woodcliff Lake, NJ-based Autodata Corp.’s Motor Intelligence.

The seasonally adjusted annualized rate—an industry measure of the pace of sales for the calendar year—saw U.S. automakers last month on track to sell 14.2 million vehicles in 2012.

Irvine-based Mazda North American Operations was another local automaker to post big January gains.

Mazda saw sales up 68.2% from a year earlier to 23,996 vehicles. That’s the highest January sales have been since 1994.

Mazda attributed the sales surge to heavy holiday advertising and having the right inventory on dealer lots.

Sales of the Mazda2 sedan surged more than 500% to 3,030 vehicles last month.

The Mazda3 sedan’s sales jumped 83.4% to 9,200 vehicles.

Other OC automakers didn’t fare as well last month.

Brea-based American Suzuki Motor Corp. saw January sales down 41% from a year earlier, to 1,505 vehicles.

Suzuki’s decline was led by an 86% dip in sales of the XL7 sport utility vehicle, which is no longer being produced.

Suzuki's Kizashi sport sedan was another big decliner, with sales falling 73% last month to 253.

Cypress-based Mitsubishi Motors North America Inc. saw sales fall 17.6% from a year earlier to 4,711 vehicles.

Mitsubishi attributed the year-over-year decline to the Eclipse coupe, Eclipse Spyder convertible and Endeavor crossover vehicles, all of which it stopped producing in August.

Mitsubishi is now looking to its new i electric vehicle to help drive sales this year. The i is expected to be rolled out to dealers nationwide by the summer.