GM OBD Trouble Code 44

Oxygen Sensor Error (Lean Condition Indicated)

The ECM receives a signal from the O2 sensor based on the amount of oxygen in the exhaust. If there is excess oxygen in the exhaust, it is in lean condition and the O2 sensor voltage will be low. The ECM uses this information to adjust the amount of fuel delivered to each cylinder.

Fault Code Description

• 44 - Oxygen sensor error (lean condition indicated)
• On V-type engines with two O2 sensors, code 44 would indicate the left bank sensor is lean

Symptoms

• Lack of power

Common Problems

• Faulty O2 sensor
• Engine vacuum leak