2001 Hyundai Tiburon car starting issue

Engine Mechanical problem
2001 Hyundai Tiburon 4 cyl Two Wheel Drive Automatic 82000k miles

My 2001 tiburon will crank, but not start in weather colder that 0 degrees celsius unless the block heater is plugged in for at least an hour. Tried changing spark plugs and fuel filter, also reset air idle control. There is a p0134 code for the o2 sensor, is it possible that a failing front o2 sensor could cause this problem? If not, any ideas?