What Does P0172 Mean on Your 2022 Lincoln Nautilus?
A P0172 code on your 2022 Lincoln Nautilus indicates the PCM has detected a rich air-fuel mixture on Bank 1. The 2022 Nautilus comes with two engine options: a 2.0-liter turbocharged inline-4 producing 250 hp and a 2.7-liter twin-turbocharged V6 producing 335 hp. Both use direct injection and are paired with an 8-speed automatic transmission.
On the 2.0T inline-4, there is only one bank. On the 2.7T V6, Bank 1 is the cylinder bank containing cylinder number 1. Running rich means excess fuel in the combustion mixture.
Symptoms You May Notice
- Check engine light on
- Fuel economy below the rated 22/29 mpg (2.0T) or 19/26 mpg (2.7T)
- Rough idle
- Black exhaust smoke
- Fuel smell from exhaust
- Reduced power or hesitation
- Possible misfires
Common Causes of P0172 on the 2022 Lincoln Nautilus
- Dirty MAF Sensor - Oil vapor contamination from the turbo inlet causes inaccurate airflow readings and over-fueling.
- Boost System Leak - Charge pipe or intercooler connection leaks reduce actual airflow reaching the engine.
- Leaking Fuel Injector - Direct injection injectors can develop leaks at high operating pressures.
- Faulty Upstream O2 Sensor - A degraded oxygen sensor provides incorrect feedback to the PCM.
How to Diagnose P0172
- Scan all codes - Check for companion codes.
- Review fuel trims - Negative LTFT beyond -10% confirms the issue.
- Clean the MAF - Cheapest first step.
- Boost leak test - Check all charge pipe connections.
- Monitor O2 sensors - Check Bank 1 upstream sensor response.
- Test injectors - Check for leaks on Bank 1.
Repair Options and Cost Breakdown
- MAF Cleaning - $15-$30 DIY.
- MAF Replacement - $170-$380 parts and labor.
- Boost Pipe Repair - $100-$420 depending on the component.
- Fuel Injector Replacement - $320-$700 per injector.
- O2 Sensor Replacement - $200-$400 parts and labor.
Most P0172 repairs on the Nautilus cost between $180 and $480. The Nautilus shares many powertrain components with other Ford products, keeping costs moderate.
Can You DIY This Repair?
MAF cleaning is straightforward. Boost hose inspection is manageable. The Nautilus engine bay varies by engine: the 2.0T is more accessible than the 2.7T V6. Injector work on either engine is best left to a Ford/Lincoln specialist.
Prevention Tips
- Replace the air filter every 15,000-20,000 miles
- Use quality fuel from top-tier stations
- Add fuel system cleaner every 10,000 miles
- Have turbo components inspected during service
- Address check engine lights promptly