P2198: Oxygen sensor signal biased or stuck rich (bank 2, sensor 1)
The bank 2 oxygen sensor before the catalyst reads rich and will not respond. It may be the sensor or too much fuel on that side of the engine.
| Code | P2198 |
|---|---|
| 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 P2198 means
On engines with two banks, the sensor ahead of the catalytic converter on bank 2 keeps reading rich (little oxygen) even when the ECU takes fuel away. The sensor may be contaminated or faulty, or that side of the engine is really getting too much fuel.
Most common causes
- Contaminated or worn oxygen sensor
- Sensor wiring touching another wire or shorted to voltage
- Leaking bank 2 injector
- High fuel pressure
- Purge valve open when it should not be
- Bank 2 cylinders burning oil or coolant
Symptoms
- Engine warning light on
- Fuel smell from the exhaust
- Higher fuel consumption
- Black smoke in some cases
Can you drive with P2198?
With care You can drive, but get it checked soon: if the fault is real, you burn extra fuel and the catalytic converter suffers.
Open the bonnetthe in-depth explanation
How to check it
Watch the bank 2 sensor live when you lift off the throttle while moving: on overrun it should drop to lean. If it stays rich, the sensor or wiring is at fault. Comparing with bank 1 shows whether only one side is affected.
How to read and clear P2198 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 P2198 with its description and whether it’s confirmed, pending or permanent.
If the engine stores it over standard OBD, with FREE you read this code with its explanation for nothing and clear it. With PRO you also read the faults of every control unit and clear them in all of them.
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 an inspection. It’s all in how to read and clear fault codes and in inspections and OBD.
Similar codes
- P2194 The mixture on bank 2 is too rich when the engine is under high load
- P2195 Oxygen sensor signal biased or stuck lean (bank 1, sensor 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)
- P2199 The readings from intake air temperature sensors 1 and 2 do not agree
- P219A The mixture is not the same in all cylinders of bank 1
- P219B The mixture is not the same in all cylinders of bank 2
- P219C Cylinder 1 is getting a different mixture from the others
- 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
What does code P2198 mean?
On engines with two banks, the sensor ahead of the catalytic converter on bank 2 keeps reading rich (little oxygen) even when the ECU takes fuel away. The sensor may be contaminated or faulty, or that side of the engine is really getting too much fuel.
Can you drive with P2198?
You can drive, but get it checked soon: if the fault is real, you burn extra fuel and the catalytic converter suffers.
How do you clear P2198?
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, P2198 comes back.
Read it on your car
Final OBD reads and clears engine faults through standard OBD for free, each one explained in plain English. With PRO it also reads the faults of every control unit, each make’s own codes included, and clears them in all of them.
