What Does P0171 Mean on Your 2022 Infiniti QX60?
If your 2022 Infiniti QX60 has triggered a P0171 code, the engine control module has detected a lean air-fuel mixture on Bank 1. The completely redesigned 2022 QX60 is powered by a 3.5-liter V6 (VQ35DD) producing 295 horsepower with direct injection. Bank 1 on this transverse V6 is typically the rear cylinder bank (closest to the firewall). The ECM is adding extra fuel to correct the lean condition.
Symptoms You Might Notice
- Check engine light on
- Rough or uneven idle
- Hesitation when accelerating from a stop
- Fuel economy dropping below the typical 21-26 MPG
- Engine feels less smooth than usual
- Subtle loss of power during acceleration
Common Causes of P0171 on the 2022 Infiniti QX60
The VQ35DD engine is Nissan/Infiniti's proven V6 platform with some specific lean-condition triggers:
- Vacuum Leak (35% likelihood) — Check the intake manifold gaskets, PCV valve hoses, and brake booster vacuum line. The VVEL (Variable Valve Event and Lift) system adds complexity with additional vacuum lines.
- MAF Sensor Contamination (25% likelihood) — The mass air flow sensor can get dirty from oil vapors or a contaminated air filter, causing incorrect airflow readings.
- Fuel Injector Issue (25% likelihood) — The direct fuel injectors can develop carbon deposits or fail, reducing fuel delivery to individual cylinders.
- Exhaust Leak Before O2 Sensor (15% likelihood) — An exhaust manifold crack or gasket leak near the upstream O2 sensor can fool the ECM into seeing a lean condition.
How to Diagnose the Problem
- Scan for all codes — Use a quality OBD-II scanner to check for companion codes. P0174 (Bank 2 lean) alongside P0171 indicates a system-wide issue.
- Monitor fuel trims — Check STFT and LTFT on both banks at idle and 2500 RPM. Bank-specific elevation narrows the search.
- Smoke test — The most effective method for finding vacuum leaks in the QX60's intake system.
- MAF sensor evaluation — Check readings against factory specs. Clean with MAF-specific spray first.
- Fuel pressure test — Monitor fuel rail pressure at idle and under load. The direct injection system should maintain high pressure.
Repair Options and Cost Breakdown
- Vacuum leak repair: $150–$400. DIY cost is $20–$70. Intake gaskets require moderate effort.
- MAF sensor replacement: $180–$350. Part cost is $70–$160. Easy DIY — just unplug and swap.
- Fuel injector service: $300–$700. Professional cleaning is $150–$250. Full replacement is $600–$1,200 for the affected bank.
- Exhaust manifold repair: $300–$700. Parts cost $80–$200. Rear bank access is tight on the transverse V6.
Prevention Tips
- Use premium fuel for optimal performance (recommended but not required)
- Replace the air filter every 15,000 miles
- Follow Infiniti's recommended maintenance schedule
- Have the fuel injectors professionally cleaned every 50,000 miles
- Use Infiniti-recommended oil to protect the VVEL system
Is It Safe to Drive?
You can safely drive your QX60 for daily commuting with P0171. However, the QX60 is a family vehicle often loaded with passengers, and running lean under load stresses the catalytic converters. Get it checked within two weeks.