P0175 on the 2022 Lincoln Nautilus: What's Happening Under the Hood
The 2022 Lincoln Nautilus offers two turbocharged engine options: the 2.0L EcoBoost four-cylinder (250 hp) and the 2.7L EcoBoost V6 (335 hp). Both are paired with an 8-speed automatic transmission. When P0175 appears, the PCM has detected that the fuel system is running too rich — more fuel than the stoichiometric ratio requires. On the V6, bank 2 is one side of the engine. On the four-cylinder, the secondary fuel control loop detects the excess.
Symptoms in Your Nautilus
- Check engine light on the Nautilus's 13.2-inch center screen or digital cluster
- Fuel economy below the rated 22/29 MPG (2.0T) or 19/26 MPG (2.7T)
- Dark exhaust smoke during acceleration
- Rough idle — noticeable in the Nautilus's hushed cabin
- Fuel smell from the exhaust
- Turbo boost feels inconsistent or sluggish
Common Causes on the Nautilus EcoBoost Engines
1. MAF Sensor Contamination
Both EcoBoost engines use hot-wire MAF sensors that are sensitive to contamination. Road dust, oiled aftermarket air filters, and PCV blow-by are common contamination sources. On both turbo engines, MAF errors propagate through boost calculations, making accurate readings essential. Cleaning costs $10–$15; Ford/Lincoln OEM MAF runs $115–$270.
2. Boost System Leak or Wastegate Issue
The EcoBoost charge system includes intercooler piping, hose connections, and electronically controlled wastegates. Boost leaks from loose connections or a wastegate that doesn't regulate properly cause the PCM to miscalculate cylinder filling. The 2.7L V6 has more charge piping than the 2.0L four, offering more leak points. Boost leak testing with smoke identifies issues. Repairs range from $80 for hose tightening to $300–$600 for wastegate work.
3. O2 Sensor Degradation
The upstream wideband O2 sensor on bank 2 provides mixture feedback to the PCM. With the 2022 Nautilus potentially having 20,000–60,000 miles, sensor degradation from age or rich exhaust exposure is possible. A slow-responding sensor keeps the PCM in a fuel-adding mode. Replacement costs $140–$310 at a Lincoln dealer, or $100–$230 at an independent Ford shop.
4. High-Pressure Fuel System Component
Both EcoBoost engines use cam-driven HPFPs and high-pressure direct injection. Ford has issued TSBs for HPFP concerns across the EcoBoost platform. Inconsistent pump pressure or an injector with incorrect flow rate causes over-fueling. HPFP replacement runs $280–$600 at a Lincoln dealer.
Diagnostic Approach
- Identify your engine (2.0T or 2.7T) — boost system diagnostics differ
- Scan for all codes including boost-related and EVAP codes
- Monitor fuel trim data — LTFT bank 2 below -10% confirms the rich condition
- Clean the MAF sensor as a quick diagnostic step
- Perform boost leak testing on the charge system
- Check for Ford TSBs applicable to your engine
Nautilus Ownership Perspective
The Nautilus is Lincoln's mid-size luxury crossover, positioned between the Corsair and Aviator. Owners expect refined, trouble-free operation. P0175 introduces engine roughness and reduced performance that undermines the luxury experience. The Nautilus's catalytic converters cost $900–$2,200 each, making timely repair financially sensible. The 2022 model may still be within the 4-year/50,000-mile bumper-to-bumper or 5-year/60,000-mile powertrain warranty.
Lincoln Dealer vs Independent
Lincoln dealer labor runs $150–$215/hour. The Nautilus shares its EcoBoost engines with Ford Edge (2.0T) and Ford Explorer (2.7T predecessor), so parts are widely available from aftermarket suppliers. An independent Ford specialist can save 25–40% on labor while using equivalent parts. For warranty-eligible repairs, the dealer is the obvious choice. Check your coverage before paying out of pocket.