OBD-II code · Powertrain (generic)
P014D O2 Sensor Slow Response - Lean to Rich Bank 1 Sensor 1
Pre-cat O2 sensor on bank 1 responds too slowly when mixture transitions from lean to rich. 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 P014D?
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
- P013BO2 Sensor Slow Response - Lean to Rich Bank 1 Sensor 2
- P013DO2 Sensor Slow Response - Lean to Rich Bank 2 Sensor 2
- P014FO2 Sensor Slow Response - Lean to Rich Bank 2 Sensor 1
- P014AO2 Sensor Delayed Response - Rich to Lean Bank 2 Sensor 2
- P014BO2 Sensor Delayed Response - Lean to Rich Bank 2 Sensor 2
- P014CO2 Sensor Slow Response - Rich to Lean Bank 1 Sensor 1
- P014EO2 Sensor Slow Response - Rich to Lean Bank 2 Sensor 1
- P0150O2 Sensor Circuit Malfunction (Bank 2, Sensor 1)
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.