Question

I have a 2003 Oldsmobile Aurora showing error codes P0138 and P0140 what is the cure?

Answer 1

P0138 Oxygen sensor circuit high voltage bank 1 sensor 2, (this is a catalytic monitor)

P0140 Oxygen sensor bank 1 sensor 2 ,no activity,(which mean its dead)

Here is the fix P0138 either the wire somehow is disconnected externally or internal that sensor is dead,wire on the outside looks good replace the sensor,as fo P0140 you replace it and again inspect the wires make sure its in good shape,these are both downstream sensor meaning it after the catalytic convertor