Reduced engine power warning when colder than -20 outside?

When it is colder than -20 outside my car goes into limp mode, engine power reduced and then care is 0-100 in like 10 mins, its horrible. The transmission also takes longer to shift between gears at cold temps. Car works beautifully all year until winter hits. What could be causing this issue? How do I fix it? I cannot afford to get my car into a shop at this time.