My car has been running like crap for the last couple of days, so I took it to a friend that works at a local shop to pull the codes. Low vooltage o2 sensor came up and lean-part throt., does this mean the o2 sensor is bad and if so can the other code be a result of a bad o2 sensor?

 

Have him watch the sweep/switching rate of the O2, and make sure it's not lazy, and to see if the car is running rich/lean.