P1133
HO2S Insufficient Switching Sensor 1
Severity
⚠️ MediumCan you drive?
Yes, but get it checked soon
Approx. repair cost
$17–56 (est.)
Symptoms
- Increased fuel consumption
- Unstable engine idling
- Reduced engine power
- Check engine light comes on
- Increased emissions of harmful substances
Causes
- Oxygen sensor malfunction
- Open or short circuit in the sensor circuit
- Poor contact in the sensor connector
- Air leak in the exhaust system
- Fuel system problems (too rich or lean mixture)
How to Fix
- Check the condition of the oxygen sensor and its connector
- Check the integrity of the wiring to the sensor
- Check the exhaust system for leaks
- Check fuel system operating parameters
- If necessary, replace the oxygen sensor