Are you talking about the sour cream you put on top of the cheesecake or does your recipe call for sour cream in the batter? If its just on top, leave it off, if its in the batter then yes, you can sub the yogurt. I have a recipe that doesn't have sour cream in it. Everyone has always enjoyed it.
NewYork Style Cheesecake
Preheat oven to 300 degrees F.
3 cups graham cracker crumbs
6 oz butter, melted
Blend together and press into 9 inch springform pan. Press crumbs
approx. 2 inches up sides of pan.
32 oz cream cheese, softened
1 2/3 cups sugar
4 large eggs
2 tsp vanilla
Mix cream cheese and sugar until lump free and smooth. Add eggs, one
at a time, mixing well. Add vanilla and beat until smooth. Pour into pan
and bake until center puffs and no longer shakes when pan is moved.
Approx. 1 hour and 20 minutes at 300 degrees F.
Cool in pan and unmold.
NOTE: To make a marbled cheesecake, reserve 2 cups of batter and add
3 oz of semi-sweet or bittersweet chocolate, melted. Pour plain batter into
pan, pour the chocolate batter over and swirl with a spatula and bake as
Recipe courtesy of California Culinary Academy, San Francisco, CA.