P1138
Lack Of Heated Oxygen Sensor Switches Bank 1 Sensor 2 Switch Indicates Rich
Severity
⚠️ MediumCan you drive?
Yes, but get it checked soon
Approx. repair cost
$28–89 (est.)
Symptoms
- Increased fuel consumption
- Unstable engine operation at idle
- Check Engine light comes on
- Reduced engine power
- Black smoke from the exhaust pipe
Causes
- Malfunction of the oxygen sensor bank 1 sensor 2
- Open or short circuit in the sensor circuit
- Fuel system problems (mixture too rich)
- Sensor contamination due to oil or coolant leak
- Malfunction of the catalytic converter
How to Fix
- Check the condition of the oxygen sensor bank 1 sensor 2
- Check the continuity of the sensor circuit and connectors
- Check the fuel system for leaks
- Clean or replace the oxygen sensor
- Check the condition of the catalytic converter