well my 98 jeep keeps throwing a o2 sensor code p0135 which i know is the front o2 sensor so i changed it but the code keeps poping up and when i clear the code the jjep runs like crap and it has a hard time accerating also just once it poped up with p0138 which is the back o2 sensor but that was only once. does anybody have any answers please?

 

Some O2 sensor are preheated and it not a problem with system. I would check for shorted wire or wire touching exhaust system.Front or rear o2 senser.