So about a month ago I started noticing that every now and then my car would run rough on start up after been sitting for a couple of hours. Once in closed loop it would run fine. I didn't think nothing of it until it started doing it more and more. About 2 weeks ago my car pulled a code for bank 1 sensor 1 high voltage which means running rich, code P0132. So I checked it and then replaced with a new one yesterday since I finally had free time. Today I started her up and once again rough idle until closed loop. Once in closed loop runs perfect no hiccups at all. What else could be the problem? I cleaned Mass air flow sensor yesterday thinking that could also be it, but still runs rough on start up. Maybe one of you guys can help. Thanks!