P2198 – O2 Sensor Signal Biased/Stuck Rich (Bank 2 Sensor 1)
Description
The upstream oxygen sensor on Bank 2 is stuck indicating a rich condition. This causes incorrect fuel trim adjustments and may lead to poor fuel economy.
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View Recommended ScannersSymptoms
- Poor fuel economy
- Black exhaust smoke
- Rough idle
- Hesitation
- Check engine light
Causes
- Faulty O2 sensor
- Leaking injector
- High fuel pressure
- Wiring issues
Diagnosis
- Check O2 sensor voltage
- Inspect injectors
- Monitor fuel pressure
- Check wiring
Repair
- Replace O2 sensor
- Repair wiring
- Replace leaking injector
