Question

2004 Chevrolet Trailblazer 4.2L V6 with engine code P0140, what is the best reapir?

Answer 1

This code is for an issue with the rear O2 sensor heater voltage. This could indicate and issue with the power wire to the heater on the sensor, or the sensor heater has failed and the sensor should be replaced. This is difficult to diagnose without the use of a scan tool that can read the live data from the sensor.

Answer 2

P0140 CHEVROLET - O2 Sensor Circuit No Activity Detected Bank 1 Sensor 2
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