The Ford F-150 pickup truck, the best-selling vehicle in the United States, is under National Highway Traffic Safety Administration scrutiny. The NHTSA has opened preliminary investigation into 400,000 of the perennially popular trunks from 2011-2013 for acceleration problems.
The NHTSA has received 95 reports of incidents of reduced engine power during hard accelerations in 2011-2013 Ford F-150 trucks equipped with 3.5-liter gasoline turbocharged direct injection engines.
Some complaints allege unexpected sharp reductions in engine power during hard accelerations at highway speeds, such as attempted merging or passing maneuvers.
NHTSA said Ford has issued three technical service bulletins related to intermittent stumble/misfire on acceleration from highway cruise in humid or damp conditions in some 2011 and 2012 F-150 vehicles equipped with 3.5L GTDI engines.
The most recent bulletin includes procedures for diagnosing a condition related to moisture accumulation in the Charge Air Cooler during extended highway cruising at constant throttle in humid or damp conditions; and repairing the condition by reprogramming the powertrain control module with the latest calibration and installing a new CAC and air deflector plate.
NHTSA said one-third of the reports received say the incidents occurred while driving in humid or rainy conditions. Many complaints allege safety concerns associated with overtaking vehicles. No crashes have been reported in connection with the issue.
Ford’s most recent technical service bulletin was issued on March 18. It notified dealers that the F-150 has an adaptive transmission shift “which allows the vehicle’s computer to learn the transmission’s unique parameters and improve shift quality. When the adaptive strategry is reset, the computer will begin a relearning process. This re-learning process may result in firmer than normal upshifts and downshifts for several days.”
Ford is cooperating with the NHTSA, according to a manufacturer spokesman.