I recently checked on my truck and got the engine code :P0138 (M) 1/2 O2 Sensor Shorted To Voltage Oxygen sensor input voltage maintained above normal operating range.Can anyone tell me what this means and how I can correct it? Is it just an O2 bad, Which one? thanks

 

check the wiring to make sure your not shorting one but yea mostly likely your o2 sensor is bad.

 

that's what I thought because I cant see it shorted anywhere. Is there anyway at all I can tell which O2 it is? thanks adam