P2195: Oxygen sensor signal biased or stuck lean (bank 1, sensor 1)
The bank 1 oxygen sensor before the catalyst reads lean and will not respond. It may be the sensor itself or a real air leak.
| Code | P2195 |
|---|---|
| System | Engine and transmission |
| Group | P21xx, Throttle, injection and emissions |
| Type | Generic: it means the same on every make |
| Can you keep driving? | With care |
What P2195 means
The oxygen sensor measures oxygen in the exhaust so the ECU can adjust the mixture. Here the sensor ahead of the catalytic converter on bank 1 keeps reading lean (a lot of oxygen) even when the ECU adds fuel. Either the sensor is faulty or air really is getting in, or fuel is short.
Most common causes
- Exhaust leak ahead of the sensor letting air in
- Intake air leak (vacuum hose, gasket)
- Worn or contaminated oxygen sensor
- Damaged sensor wiring or connector
- Low fuel pressure or dirty injectors
- Air flow sensor reading less air than is going in
Symptoms
- Engine warning light on
- Rough idle
- Lack of power
- Fuel consumption slightly off
Can you drive with P2195?
With care The car can be driven, but the ECU may be adding too much fuel to compensate. Get it checked soon to avoid extra consumption or catalyst damage.
How to check it
Watch the bank 1 sensor 1 signal and fuel trims live. If a sharp blip of the throttle does not make the sensor swing rich, suspect the sensor; if it responds but trims are very positive, look for an air leak or a fuel supply problem.
How to read and clear P2195 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see P2195 with this same explanation and whether it’s confirmed, pending or permanent.
With Free you read this code with its short description for nothing, and clear it if the engine stores it over standard OBD. With Pro you get the full explanation, how the car was running when it was logged (revs, temperature, load) and clearing in every control unit.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before the ITV. It’s all in how to read and clear fault codes and in the ITV and OBD.
Similar codes
- P2187 Mixture too lean at idle (bank 1)
- P2188 Mixture too rich at idle (bank 1)
- P2189 Mixture too lean at idle (bank 2)
- P2191 Mixture too lean at higher load (bank 1)
- P2196 Oxygen sensor signal biased or stuck rich (bank 1, sensor 1)
- P2197 Oxygen sensor signal biased or stuck lean (bank 2, sensor 1)
- P2198 Oxygen sensor signal biased or stuck rich (bank 2, sensor 1)
- P2100 Throttle actuator A control motor circuit open
- P2101 Throttle actuator A control motor circuit range or performance
- P2102 Throttle actuator A control motor circuit low
- P2104 Throttle control system: forced idle
P2195 is a generic code, so it means the same on any make, for example on Audi, BMW, Fiat, Mazda, Peugeot, Volkswagen. See what Final OBD does on your car in makes and models.
What does code P2195 mean?
The oxygen sensor measures oxygen in the exhaust so the ECU can adjust the mixture. Here the sensor ahead of the catalytic converter on bank 1 keeps reading lean (a lot of oxygen) even when the ECU adds fuel. Either the sensor is faulty or air really is getting in, or fuel is short.
Can you drive with P2195?
The car can be driven, but the ECU may be adding too much fuel to compensate. Get it checked soon to avoid extra consumption or catalyst damage.
How do you clear P2195?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, P2195 comes back.
Read it on your car
Final OBD reads the faults of every control unit for free, including each make’s own codes, and with Pro explains each one in plain English. Free clears engine faults at no cost.
Coming soon
Mid to late October 2026
If you want to try it in your car before anyone else, send us your email and we will add you as a tester.
info@finalobd.com