P0139 Mazda -

Question

Sir I have engine light on. Took it to two auto repair shops and their scan came back with the same error. P0139. Is it hard to replace this sensor and where is the best place to get this part. I have a Mazda5 2010 sport. Thanks.

Answer 1

if your car is under warranty it will be covered by Mazda. I would suggest you but the orginal sensor either if its not covered by the Emisson warranty 

it might take 30min or so to replace it, assuming the problem is the oxygen sensor and not the other possible causes:

Possible causes

- Faulty Rear Heated Oxygen Sensor Bank 1

- Rear Heated Oxygen Sensor Bank 1 harness is open or shorted

- Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection

- Inappropriate fuel pressure

- Faulty fuel injectors

- Intake air leaks may be faulty

- Exhaust gas leaks