One problem related to engine overheat has been reported for the 2012 Ford Fusion. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2012 Ford Fusion based on all problems reported for the 2012 Fusion.
My 17 yr old daughter was driving the car at 30 mph when the car began to buck and jerk and she immediately brought it to a stop. It would not take any more power or acceleration. While stopped in the middle of the road she called me and noted the temp gauge showed hot with a check engine light. We had it towed. Technician who diagnosed the problem found a faulty temp sensor that showed the engine was overheating and causing the engine to go into fail-safe shut-down mode. Apparently this has happened often enough that Ford has a service bulletin out on the problem, but no recall. This could have been a disaster if she had still been on the road where she parked it. There should be a manufacturer recall to have these parts checked out. There is a known corrosion issue with the sensor and wiring.