Question

My 2004 Nissan Sentra 1.8L display P1146, P0138, P1146 and 0138

Answer 1

Both code are related to the Rear O2 sensor. You probably need a new rear O2 sensor.

P0138 NISSAN - HO2S12 Circuit High Voltage

Read More: https://www.autocodes.com/p0138_nissan.html

P1146 NISSAN - Heated Oxygen Sensor 2 Minimum Voltage Monitoring Bank 1

Read more: https://www.autocodes.com/p1146_nissan.html