What Does P0172 Mean on Your 2022 Nissan Pathfinder?
A P0172 code on the 2022 Nissan Pathfinder means the engine control module has detected a rich fuel condition on Bank 1. The completely redesigned 2022 Pathfinder uses the 3.5L VQ35DD V6 engine producing 284 horsepower, now paired with a 9-speed automatic transmission instead of the previous CVT. Bank 1 on this V6 is the rear bank closest to the firewall.
A rich condition wastes fuel, fouls spark plugs, and can damage the catalytic converter. The 2022 Pathfinder may still be under powertrain warranty, so a dealer visit is worth considering.
Common Symptoms You May Notice
- Check engine light illuminated
- Lower fuel economy
- Rough or fluctuating idle
- Black exhaust smoke
- Gasoline odor at the tailpipe
- Reduced power
Top Causes of P0172 on the 2022 Pathfinder
- Contaminated MAF sensor - Dust and debris contaminate the MAF element, causing underreported airflow and excess fuel injection.
- Degraded upstream O2 sensor - The Bank 1 upstream oxygen sensor may be defective or degraded, sending incorrect signals.
- Leaking fuel injector - A direct injection injector on the rear bank that fails to close properly delivers excess fuel.
- EVAP purge valve stuck open - A malfunctioning valve sends continuous fuel vapors into the intake.
How to Diagnose the Problem
Scan codes and check freeze frame data. Review Bank 1 STFT and LTFT. Negative LTFT past -10% confirms the rich condition.
Clean the MAF sensor with proper cleaner. Monitor the Bank 1 upstream O2 sensor; it should toggle between 0.1V and 0.9V. If only Bank 1 is rich, focus on rear bank components.
Repair Options and Cost Estimates
- MAF sensor cleaning or replacement: Cleaning under $10. New sensor $45-$155 plus $40-$95 labor.
- O2 sensor replacement: Parts $45-$150. Labor $70-$145.
- Fuel injector replacement: Parts $35-$100 per injector. Labor $180-$390.
- EVAP purge valve: Parts $20-$55. Labor $45-$95.
Can You Fix This Yourself?
MAF cleaning is easy. O2 sensor replacement is moderate. The 2022 Pathfinder may still be under warranty, so consider dealer service first.
Prevention Tips
- Replace the air filter on schedule
- Use quality fuel to keep direct injectors clean
- Run fuel system cleaner periodically
- Address check engine lights promptly