OBD-II code · Powertrain (generic)
P0133 O2 Sensor Slow Response (Bank 1, Sensor 1)
The upstream oxygen sensor switches between rich and lean too slowly. Aged sensors lose response speed before they fail outright; this code typically appears before P0130/P0131/P0132.
Is it safe to drive with P0133?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelyOxygen sensor aged
- PossibleSensor partially poisoned (silicone, lead, sulphur)
Symptoms
- Check engine light on
- Increased fuel consumption
- Possible rough idle or hesitation
- Failed emissions test
Repair at a glance
- Difficulty
- Easy
- DIY friendly
- Often, with basic tools
- Typical labour
- 0.3–1.5 h
- Emissions test
- Likely to fail
- After the fix
- A drive cycle is needed before the light stays off
- Parts involved
- Oxygen Sensor Upstream
Related codes
- P0130O2 Sensor Circuit Malfunction (Bank 1, Sensor 1)
- P0131O2 Sensor Circuit Low Voltage (Bank 1, Sensor 1)
- P0132O2 Sensor Circuit High Voltage (Bank 1, Sensor 1)
- P0134O2 Sensor Circuit No Activity / Slow Response (Bank 1 Sensor 1)
- P0135O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1)
- P0136O2 Sensor Circuit Malfunction (Bank 1, Sensor 2)
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.