OBD-II code · Powertrain (generic)
P014C O2 Sensor Slow Response - Rich to Lean Bank 1 Sensor 1
Pre-cat O2 sensor on bank 1 responds too slowly when mixture transitions from rich to lean. A drifted or sluggish lambda sensor lets the mixture run lean or rich without correction — fuel economy and emissions suffer immediately.
Is it safe to drive with P014C?
Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.
Common causes
- Most likelySensor aged
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 B1s1
Related codes
- P013AO2 Sensor Slow Response - Rich to Lean Bank 1 Sensor 2
- P013CO2 Sensor Slow Response - Rich to Lean Bank 2 Sensor 2
- P014EO2 Sensor Slow Response - Rich to Lean Bank 2 Sensor 1
- P0149Fuel Timing Error
- P014AO2 Sensor Delayed Response - Rich to Lean Bank 2 Sensor 2
- P014BO2 Sensor Delayed Response - Lean to Rich Bank 2 Sensor 2
- P014DO2 Sensor Slow Response - Lean to Rich Bank 1 Sensor 1
- P014FO2 Sensor Slow Response - Lean to Rich Bank 2 Sensor 1
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.