Has the six cylinder 1mz-fe motor

Has the six cylinder 1mz-fe motor. The motor has 160k and ran strong, no faults.
cruising along at 75 in cruise control, and the car shifted out of o.D. And the engine started to skip, the check engine light started flashing. I was far from an exit and the car still ran.
the car made it home, some times really well (especially under load) and some times not so smooth, the check engine light on steady and some times flashing, but running and not using any extra oil, gas milage is worse by 10% or so. Now that it sat for 4 days in the 10-20 degree cold, it doesnt't want to start at all. Any ideas