Engine misfire could be caused by worn or broken motor mounts that raise the motor on one side while the vehicle is accelerating. The stress on the engine control wiring harness can cause breaks in the injector or sensor wires, which then causes driveability concerns such as poor fuel economy and engine misfires.
Car Problem Reports
Mercury Cougar Engine misfire due to damaged engine wire harness
Mercury Cougar Problem
Engine Affected: 4.6L V8