One problem related to engine stall has been reported for the 2010 Ford Focus. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2010 Ford Focus based on all problems reported for the 2010 Focus.
Engine stalls while driving and will not restart. I suspect that it is related to similar issues drivers are having with the evap canister purge valve in other model years: "the canister purge valve may malfunction and create excessive vacuum in the fuel vapor management system, which can result in the engine stalling without restarting. Dealers will reprogram the powertrain control module and replace the canister purge valve as needed. If the valve needs to be replaced, dealers will also inspect and replace the carbon canister, fuel tank and fuel delivery module as determined to be needed. All repairs will be performed free of charge to resolve the concern. ".