What Does P0171 Mean on a 2020 Nissan Murano?
A P0171 code on your 2020 Nissan Murano means the engine control module detected a lean air-fuel mixture on Bank 1. The 2020 Murano is powered by a 3.5L V6 engine (VQ35DE) producing 260 horsepower paired with a CVT. On this V6, Bank 1 is one of the two cylinder banks. The code means too much air or too little fuel on those cylinders.
The VQ35 in the Murano is detuned slightly compared to the Maxima version, but it faces the same potential lean condition causes. Let's look at what's most likely going on.
Symptoms You Might Notice
- Check engine light on
- Rough idle
- Hesitation during acceleration
- Decreased fuel economy
- Engine surging
- Possible misfires
Common Causes of P0171 on the 2020 Nissan Murano
- Dirty MAF Sensor (30% likelihood) - Contamination of the mass airflow sensor is the number one cause on Nissan V6 engines.
- Vacuum Leak (25% likelihood) - Intake manifold gaskets, PCV hoses, and vacuum lines deteriorate over time.
- Fuel Injector Wear (25% likelihood) - Port fuel injectors can develop restricted flow patterns with age.
- Oxygen Sensor Issue (20% likelihood) - A sluggish upstream O2 sensor on Bank 1 can cause lean fuel calculations.
How to Diagnose the Problem
- Scan for all codes - Check for P0174, misfire codes, and O2 sensor codes.
- Monitor fuel trims - Compare Bank 1 and Bank 2 LTFT. Differences point to bank-specific issues.
- Clean the MAF sensor - Cheapest first step with MAF cleaner spray.
- Smoke test - Find vacuum leaks in the intake system.
- Test O2 sensors and fuel pressure - Check for sluggish sensors and adequate fuel delivery.
Repair Options and Cost Breakdown
- MAF sensor cleaning/replacement - $50 to $280.
- Vacuum leak repair - $150 to $450. Gasket work on the V6 takes some labor.
- Fuel injector cleaning or replacement - $200 to $500.
- O2 sensor replacement - $150 to $400.
Can You DIY This Repair?
MAF cleaning is easy on the Murano. Vacuum hose checks are straightforward. O2 sensor replacement needs basic tools and jack stands. Intake and injector work on the transverse V6 is more challenging.
Prevention Tips
- Clean the MAF sensor annually
- Replace the air filter every 15,000-20,000 miles
- Use Top Tier gasoline
- Inspect vacuum hoses during oil changes
- Follow Nissan's recommended maintenance schedule