NHTSA announced it was opening a preliminary investigation after receiving 95 complaints of unexpected power loss during hard acceleration of the turbocharged, direct injection engines. In some cases the engine stumbled or misfired during such maneuvers as merging or passing during highway cruising in rainy or humid conditions, prompting the concern.
Since last year, Ford has issued three technical bulletins on the problem but has not issued a recall.
"We will be cooperating with NHTSA on this investigation, as we always do," Ford spokeswoman Kelli Felker told The Detroit News.
No accidents or injuries been blamed on the acceleration problem involving the segment leading F-Series pickups, the best-selling light truck in the United States since 1982.
Sales of F-Series pickups were 19 percent higher through May compared to the same period a year earlier and Ford is adding production at its Kansas City, Mo., assembly plant.
Ford to end production in Australia
After more than 85 years of manufacturing "down under," Ford Motor Co. says it will stop making vehicles in Australia in 2016.
Ford assembly plants in Broadmeadows and Geelong are scheduled to close idling 1,200 workers. Ford has lost nearly $600 million in Australia since 2010, including $141 million in the last year.
"Our costs are doubled that of Europe and nearly four times Ford in Asia," Bob Graziano, president and chief executive officer of Ford Australia, told the Australian Broadcasting Corp. "The business case simply did not stack up. Leading us to the conclusion [that] manufacturing is not viable for Ford in Australia in the long-term."
The Ford Falcon brand will disappear when the plants close. Ford Australia, the country's third largest automaker, was founded in 1925 when Model T cars rolled off assembly lines in Geelong.
"All of us at Ford remain committed to our long history of serving Australian customers with the very best vehicles that deliver cutting-edge technology at an affordable cost," Graziano said in a statement. "Unfortunately, due to challenging market conditions we are unable to do that longer-term while continuing to manufacture locally."
Australians purchase some 1.1 million new vehicles annually, and the weak Japanese yen has given Asian automakers a comparative advantage by reducing the cost of imported vehicles. The value of the Australian dollar has gone up 29 percent compared to the yen.
"Given the fragmented marketplace and the low model volumes that result, we decided that manufacturing locally is no longer viable," Graziano said.
Ford said it plans to maintain its network of more than 200 dealers in Australia, retain more than 1,500 research and development jobs and introduce three updated models of Australian cars.
Last year, the Australian government gave Ford a $34 million subsidy to keep the plants running "at least until the end of 2016."
"This is a sad day for the workers at Ford who have heard the news today their jobs will come to an end in October 2016," Prime Minister Julia Gillard said. "This is a very sad day for those workers and for their families."
General Motors' Holden subsidiary announced plans to cut 500 jobs in Victoria and South Australia last year.
Most complained about vehicles
The folks at 24/7 Wall Street crunched some numbers from the National Highway Traffic Safety Administration to find the 10 cars that get the most complaints.
Some vehicles making the list were surprises since they are among the most popular top-selling brands. The complaints ranged from problems with electronics, brakes and engines to airbags and seat belts.
At No. 10 was South Korea's Hyundai. Hyundai sold nearly 3.7 million cars from 2005 to 2012, but got 27.96 complaints for 100,000 Hyundai's sold. The biggest offender was the Sonata.
No. 9 was Ford Motor Co., the best-selling make in the United States for the last three years. Ford averaged 33.95 complaints per 100,000 vehicles sold, with the Escape SUV getting the most complaints.
No. 8 was Germany's Volkswagen, which had 34.52 complaints per 100,000 sold, led by complaints about the Jetta.
No. 7 was Germany's BMW with 36.78 complaints per 100,000 vehicles sold. Of the 676 complaints made regarding BMW's last year, 175 were about airbags and seat belts. The 3 Series got the most complaints.
No. 6 Japan's Nissan, which had 38.89 complaints per 100,000 cars sold from 2005 to 2012, with the most complaints about the popular Altima sedan.
No. 5 Dodge, with 39.21 complaints per 100,000 sold, 653 of the 2,304 complaints against Dodge vehicles in 2012 involved the power train, with the biggest gripe involving interior electronics and hardware of the Grand Caravan minivan.
No. 4 Chrysler, with 40.78 complaints per 100,000 vehicles sold, led by complaints involving Town & Country vans.
No. 3 Smart, with 56.59 complaints per 100,000 sold.
No. 2 Jeep, with 69.48 complaints per 100,000 vehicles sold. Complaints against Jeep products involved power trains, interior electronics, hardware, suspensions and axles, fuel, emission and exhaust systems and steering problems with Wrangler garnered the most complaints.
No. 1 was Mini, the sporty car with BWM-engineered suspension, steering and brakes. Mini vehicles had 123.6 complaints per 100,000 vehicles sold, with the Cooper receiving the most complaints, steering topping the list.
2014 'Vette' rated at 455 hp
The LT1 6.2-liter V-8 engine in the base 2014 Corvette Stingray has been officially rated at 455 horsepower with 460 pound-feet of torque.
That makes the seventh-generation "Vette" the most powerful base Corvette ever. An optional performance exhaust system boosts power to 460 horsepower and 465 pound-feet of torque.
Besides the power, up 25 horses and 36 foot-pounds of torque from the current LS3 6.2-liter V-8 engine, the direct-injection V-8 also can electronically shut down some cylinders to improve fuel economy to more than 26 mpg. The Corvette has a seven-speed manual transmission driving the rear wheels or a six-speed automatic with paddle shifters.
"The 2014 Corvette Stingray's LT engine is a triumph of advanced technology, delivering more power and torque than ever before with greater efficiency," Jordan Lee, General Motors' small-block engine head, said in a statement.
The Stingray coupe goes on sale this fall starting at $51,995, including destination charges and a $56,995 Stingray Convertible will be available later this year.
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