P0145
O2 Sensor Circuit Slow Response Bank 1 Sensor 3
Fuel & air metering (O2 sensor)
Generic OBD-II
Medium
What it means
P0145 means the bank 1, sensor 3 oxygen sensor is switching between rich and lean too slowly. This is a downstream (post-catalyst) sensor, so a lazy signal mainly affects emissions monitoring and fuel trim rather than drivability. As oxygen sensors age they naturally slow down; wiring faults or an exhaust leak near the sensor can cause the same reading.
Medium
Can I keep driving? Safe to drive — a slow downstream oxygen sensor mainly affects emissions and fuel economy, not how the car runs.
Common symptoms
What you'll notice
- Check-engine light on
- Slightly increased fuel consumption
- Failed emissions test
- Little or no change in how the car drives
Common causes
Most likely first
- Aged or contaminated oxygen sensor (bank 1, sensor 3)Likely
- Exhaust leak near the sensorCommon
- Damaged or corroded wiring in the sensor circuitCommon
- Loose or poor sensor connectionLess often
- Failed ECM (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and confirm the code points to bank 1, sensor 3.
- Inspect the sensor wiring and connector for damage or corrosion.
- Check for exhaust leaks upstream of the sensor.
- Replace the oxygen sensor if it responds slowly with good wiring.
- Consider the ECM only after wiring and sensor check out.
FAQ
Quick answers
Is it safe to drive with P0145?+
Yes — a slow-responding oxygen sensor won't leave you stranded. It will cost a little extra fuel and fail an emissions test, so fix it before the test or a long trip.
Can I just clear P0145?+
It will come back after a few drive cycles unless the sluggish sensor or its wiring is repaired.
Related codes
Often seen with P0145
Read & clear P0145 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX