P2198 - O2/A-F Sensor Signal Stuck Rich (B2S1)

Upstream O2/A-F sensor signal stuck rich (bank 2).

Code Overview

Upstream O2/A-F sensor signal stuck rich (bank 2).

Common Causes

• Vacuum/exhaust leak
• Fuel delivery issue
• Sensor fault
• Injector/pressure issue

Diagnostic Steps

1. Check fuel trims
2. Inspect vacuum/exhaust leaks
3. Verify sensor response on scan tool
4. Check fuel pressure if needed

Likely Repairs & Cost Guides

Use test results to confirm the fault before pricing the repair.

Related OBD Codes

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Next Steps

Move from the code to a diagnosis path, then into repair pricing once the fault is confirmed.