Faulty software may not respond as needed when a malfunctioning valve sticks open, Ford says.
Affected vehicles include previously recalled 2012 through 2017 Focus cars equipped with the 2.0-litre GDI engine; and 2013 and 2014 Focus ST trims with the 2.0-litre GTDI. Owners may notice an engine warning light, erratic fuel gauge, or loss of power.
"Ford is not aware of any reports of accident or injury related to this condition", the company says. Affected Focus models were built at the Michigan Assembly Plant in Wayne between October 7, 2010 and July 23, 2012; August 24, 2016 to April 13, 2017 and May 3, 2012 and December 11, 2014.More news: AMLO cleans house: Mexican finance minister quits via Twitter
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Technicians have been instructed to inspect each vehicle and reprogram the powertrain control module with the appropriate software calibration and replace the canister purge valve, if required.
"If the canister purge valve is replaced, dealers will inspect and replace the carbon canister, fuel tank and fuel delivery module, as necessary", Ford adds in its release.
Ford said owners with affected vehicles should keep fuel tanks at least half full until the software is updated.