2004 dodge caravan stalls and sputters?

My 2004 dodge caravan 3.8L stalls and sputters. Some days I can drive for an hour with no problems and some days it stalls often. It dies when coming to a stop, turning & even on the freeway. It usually starts back up, but sometimes it takes a few minutes to restart. Furthermore, the other day it wanted to stall, and when I gave it gas the minivan started lurching and wouldn't go past 10-20 mph. I do have a low catalytic efficiency code coming up, but I know my catalytic converter is not bad. Not sure if a O2 sensor would cause these problems either.