P0174 Code: Honda CR-V (2017-2023) - Causes, Symptoms & Fixes

Diagnostic guide for P0174 on 2017-2023 Honda CR-V

Important data note based on the provided NHTSA data:

• Owner complaints: No NHTSA complaints found for this make/model/year/issue combination.
• Official recalls: No recalls found in NHTSA database.
• No recalls found in NHTSA database (as required by the data you supplied).
• Limitations: The data above do not capture all possible issues or local service advisories. Use the guide as a diagnostic framework alongside factory service information for your exact vehicle.

CODE MEANING AND SEVERITY

• Code meaning: P0174 = System Too Lean (Bank 2). In OBD-II terms, the engine management system is detecting a lean condition on the indicated bank and is compensating with fuel trim adjustments.
• Severity and typical consequences:
  • Symptoms may include rough idle, hesitation or stalling, reduced power, and decreased fuel economy.
  • If the lean condition persists or is severe, it can overwork the catalytic converter or lead to misfires, which may trigger additional codes (for example, P0300-series misfire codes).
  • In some cases, intermittent lean conditions can be caused by small vacuum leaks or sensor faults that don’t trigger immediate harm but will affect drivability and efficiency.

COMMON CAUSES ON HONDA CR-V (2017-2023)

Note: Lean conditions are almost always caused by either too much air, not enough fuel, or a sensor that’s giving an incorrect reading. For the CR‑V with the 1.5L turbo engine and similar setups, the common culprits include:

• Vacuum leaks and air intake leaks
  • Cracked or loose vacuum hoses, PCV hose issues, cracked intake boot, broken intake manifold gasket, dry/aged silicone hoses.
• Mass Air Flow (MAF) sensor and intake air issues
  • Dirty or faulty MAF sensor, incorrect air filter installation, aftermarket intake parts causing unmetered air.
• Air-path sensors and controls
  • Faulty or dirty MAP sensor (if equipped on the engine variant), incorrect readings affecting fuel trims.
• Fuel delivery problems
  • Low fuel pressure due to a weak fuel pump, failing fuel pressure regulator, clogged fuel filter (if externally serviceable), or injector issues causing insufficient fuel delivery.
• Oxygen sensors and engine management feedback
  • Faulty upstream O2 sensor readings, or downstream sensor feedback causing improper fuel trim calculations.
• Exhaust and EGR related
  • Exhaust leaks upstream of the O2 sensors, or EGR issues causing abnormal backpressure/flow that affects sensor readings.
• Evaporative (EVAP) and purge system
  • Evap leaks or a sticky purge valve can alter readings and fuel trim behavior in some driving scenarios.
• Turbo charging/charge-air system (for 1.5L turbo variants)
  • Boost leaks or charge-air system issues leading to increased air entering the engine without corresponding fuel delivery.
• Mechanical issues (less common but possible)
  • Compression imbalances, dirty injectors, or a failing cylinder that causes misfire conditions to be misinterpreted as a lean condition.

SYMPTOMS YOU M might notice

• Check Engine Light (malfunction indicator lamp) illuminated.
• Rough idle, especially when cold or at low RPM.
• Hesitation or lack of acceleration, particularly under load or at steady speeds.
• Reduced fuel economy.
• Occasional misfire codes (P0300 or P0301-P0306 depending on cylinder) accompanying lean condition indicators.
• OBD readiness tests may show incomplete or intermittent results if a vacuum or sensor issue is intermittent.

DIAGNOSTIC STEPS

Note: Use a scanner capable of live data to view fuel trims, sensor readings, and readouts from multiple sensors.

Step 0: Verify the DTC and data context

• Confirm the P0174 code with a scan tool, and note freeze-frame data (engine rpm, load, coolant temp, throttle position, short-term and long-term fuel trim values, etc.).
• Check for additional codes (P0171, P0172, P0173, P0175, or misfire codes P0300-P0306) that might point to a related issue.

Step 1: Visual inspection of air intake and vacuum system

• Inspect all intake hoses, clamps, the intake manifold boot, and PCV system for cracks, loose clamps, or disconnected hoses.
• Inspect aftermarket parts for leaks or mismatch.
• Look for obvious vacuum leaks around the brake booster hose and EVAP hoses.
• Check the air filter for cleanliness and correct installation.

Step 2: Inspect and test the MAF sensor and related airflow path

• If you suspect MAF contamination, remove and gently clean the MAF element with a dedicated MAF cleaner (follow product instructions). Do not touch the sensing elements with hard tools.
• Ensure the MAF wiring is intact and connector is clean and properly seated.
• After cleaning, clear codes and test drive to see if the condition returns.

Step 3: Check MAP sensor (if applicable) and related wiring

• Inspect MAP sensor connector and wiring for corrosion or loose connection.
• If you suspect a faulty MAP reading, consider testing against the service manual’s specifications or using a known-good sensor.

Step 4: Inspect fuel delivery and pressure (critical for lean conditions)

• If fuel pressure is accessible, perform a fuel-pressure test with the recommended test port and gauge to ensure it’s within the manufacturer’s spec.
• If fuel pressure is low, investigate the fuel pump, fuel filter (if serviceable), fuel pressure regulator, and potential leaks in the fuel line.
• Check regulator function and for any signs of a vacuum leak on the regulator.

Step 5: Check oxygen sensors and emissions-related sensors

• Review live data for upstream O2 sensor readings (before catalyst) and downstream O2 sensor readings (after catalyst).
• If the upstream sensor consistently shows a lean signal (high O2 sensor voltage near 0.9 V or slow-walling switching), inspect the sensor, wiring, and possible contamination.
• If the downstream sensor shows abnormal readings, verify catalytic converter efficiency; although downstream data alone won’t typically trigger lean codes, it can influence overall fuel trim behavior.

Step 6: Check for EVAP system anomalies

• Perform a visual check of purge valve and EVAP lines if available.
• Look for cracks or disconnections in lines that could create a venting issue affecting readings.
• A smoke test can be employed to reveal EVAP system leaks if the basic checks don’t locate a source.

Step 7: Check for mechanical ignition and compression concerns

• If fuel system checks are inconclusive, consider a compression test to rule out a mechanical issue that could manifest as intermittent lean conditions or misfires.
• Ensure spark plugs and ignition coils are in good condition; misfires can cause misleading lean-fuel trim readings.

Step 8: Combine data and draw conclusions

• If live data shows long-term fuel trim significantly positive (e.g., +10% to +25%+) and short-term trim is fluctuating, there is a clear lean condition likely caused by air leaks or fuel delivery issues.
• If trims are near zero and the code is intermittent, suspect intermittent vacuum leaks, wiring faults, or sensor intermittency.

RELATED CODES

• P0171: System Too Lean (Bank 1)
• P0173: System Too Lean (Bank 2) — alternative designation in some systems
• P0172: System Too Rich (Bank 1)
• P0174: System Too Lean (Bank 2) — the code in question
• P0300-P0306: Random/Multiple Cylinder Misfire (can accompany lean conditions)
• P0139 or P0141: Oxygen sensor heater or sensor-related faults that can influence oxygen readings and fuel trims

REPAIR OPTIONS AND COSTS (2025 prices)

Note: Prices vary by region, vehicle condition, and whether you DIY or hire a shop. The figures below are approximate ranges intended to help planning.

Common fixes for P0174 (lean Bank 2) and typical costs:

• Vacuum hose/PCV hose replacement
  • Parts: $5–$50
  • Labor: $40–$120
  • Notes: Quick first fix if a cracked hose is found.
• MAF sensor cleaning or replacement
  • Cleaning (DIY): often free if you already own cleaner; otherwise $5–$15 for cleaner
  • Replacement: $100–$350 parts; $50–$150 labor
• Air filter replacement and intake path fix
  • Filter: $10–$40
  • Labor (if done at shop): $20–$60
• MAP sensor replacement (if applicable)
  • Parts: $60–$180
  • Labor: $40–$120
• Oxygen sensor (upstream or downstream) replacement
  • Parts: $60–$180 each
  • Labor: $60–$150 per sensor
• Fuel system repairs (if fuel delivery is suspect)
  • Fuel pump module replacement (if bad): $300–$900 parts; $200–$600 labor
  • Fuel pressure regulator: $50–$200 parts; $60–$150 labor
  • Fuel injectors (cleaning or replacement)
    • Cleaning: $50–$150 per injector (DIY or shop cleaning)
    • Replacement (DI systems can be more expensive): $250–$700 per injector; total multi-injector costs higher
• Intake manifold gasket or major air-path seal replacement
  • Parts: $50–$250+
  • Labor: $150–$500
• Throttle body cleaning or replacement
  • Cleaning: DIY or shop: $0–$100 (if DIY; or $100–$250 if service)
  • Replacement: $300–$800
• EVAP system components (purge valve, hoses)
  • Purge valve: $40–$120
  • Labor: $60–$150
• Exhaust or catalytic converter concerns
  • Diagnostics to confirm upstream cause first; replacement costs vary widely (CAT or exhaust work can be $300–$1500+ depending on damage and vehicle).

Notes on costs for a CR-V 2017-2023:

• The 1.5L turbo CR-V uses fairly modern fuel systems and sensors. Direct injector systems and turbo components can carry higher repair costs if injector cleaning or replacement is required or if the pump/injectors need service.
• Always obtain a firm diagnosis before replacing multiple parts to avoid unnecessary costs.

DIY VS PROFESSIONAL

• DIY-appropriate tasks (if you’re comfortable with basic tools and proper safety):
  • Visual inspection of hoses, clamps, air filter; replace obvious cracked hoses.
  • Clean MAF sensor (careful handling; use dedicated cleaner).
  • Replace air filter and inspect intake components for obvious issues.
  • Basic fuel trim interpretation with a reader; some simple cleanup ideas (MAF cleaning, hose tightening) before deeper work.
• Tasks best left to a professional or at least with diagnostic equipment:
  • Fuel system pressure testing (requires a gauge and procedure per Honda service manual).
  • Accurate testing of fuel injectors and fuel delivery components.
  • Comprehensive EVAP smoke testing and advanced diagnostic scan with live data.
  • Replacement of high-cost components (OEM O2 sensors, DI injectors, high-pressure fuel system parts, turbo-related components) where exact torque specs and calibration are required.
• If you’re not experienced with high-pressure fuel systems or turbocharged engines, consider professional service after a basic inspection.

PREVENTION

• Regular maintenance helps prevent lean conditions:
  • Change air filters at recommended intervals; ensure intake paths are clean and unblocked.
  • Use high-quality fuel and maintain adequate fuel pressure by replacing pumps/filters as recommended.
  • Inspect vacuum and PCV hoses regularly; replace aging hoses before cracks develop.
  • Periodically clean MAF sensors if you habitually drive in dusty or dirty environments and ensure the sensor is properly connected.
  • Inspect EVAP system lines for cracks or leaks; address leaks promptly.
  • Address small symptoms early: a transient idle roughness or hesitation may be the first sign of a developing vacuum leak or sensor issue.

Summary and data transparency

• Based on the provided data, there are no recalls or owner complaints listed for this issue in the NHTSA data for the 2017-2023 Honda CR-V. This guide uses general automotive knowledge and standard diagnostic workflows, tailored to the CR-V’s likely 1.5L turbo engine configuration and common lean-condition causes.
• The information above is intended as a diagnostic framework. Actual vehicle symptoms, service data, and repair costs will vary by model variant, regional labor rates, and parts availability. Always cross-check with the specific Honda service manual or official Honda service information for your exact VIN and engine variant.