P0446 Code: Honda CR-V (2017-2023) - Causes, Symptoms & Fixes

Comprehensive diagnostic guide for P0446 on 2017–2023 Honda CR-V

Data note and recalls disclaimer

• REAL NHTSA DATA FOR Honda CR-V (2017-2023)
  • 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.

CODE MEANING AND SEVERITY

• Code: P0446
• Full meaning: Evaporative Emission System Vent Valve Control Circuit Malfunction (EVAP Vent Valve Control Circuit Malfunction)
• What it controls: The EVAP system stores fuel vapors from the gas tank and vents them through a vent valve/solenoid to the charcoal canister or to the intake (via the purge valve) as commanded by the PCM. P0446 specifically indicates a problem in the vent valve circuit (electrical wiring, connection, or the valve itself failing to operate properly).
• Severity and implications:
  • Emissions-related DTC; triggers the Malfunction Indicator Light (check engine light).
  • Typically does not cause an immediate safety issue or dramatic loss of power, but it can affect emissions testing, fuel economy, and may lead to a failed inspection.
  • Driving habits usually remain possible, but continued driving with an EVAP fault can mask other EVAP issues if not diagnosed properly.
• Likelihood in this model year: Based on the provided data, there are no listed recalls or complaints specific to this code for 2017–2023 CR-Vs in the source data. Do not rely on this alone for diagnostics; treat P0446 as a potentially intermittent issue requiring systematic testing.

COMMON CAUSES ON HONDA CR-V

• Faulty EVAP vent valve (solenoid) or its circuit
  • The vent valve may stick open/closed or fail to energize/de-energize as commanded.
• Damaged or corroded wiring or a faulty connector to the vent valve
  • Wiring harness damage, poor grounds, or corroded pins can disrupt the circuit.
• Faulty EVAP purge valve or related circuit
  • In some layouts the purge valve and vent valve share circuitry or control logic; a failure here can manifest as P0446 or complicate diagnosis.
• Vacuum hoses, lines, or clamps in the EVAP path are cracked, kinked, or leaking
  • Even small leaks can affect venting behavior and system pressure.
• Leaking or blocked charcoal canister
  • Canister failure or contamination can disrupt venting and system function.
• Gas cap issues (less common for P0446 alone but worth checking)
  • A loose or damaged cap can trigger EVAP codes generally; ensure the cap is tight and in good condition.
• PCM/ECU or harness fault
  • A rare but possible cause is a fault in the engine control module’s output to the vent valve or related wiring.

SYMPTOMS

• Check Engine Light (MIL) illuminated with code P0446 (and possibly related EVAP codes).
• Possible fuel odor around the vehicle (rare but possible if the system is venting improperly).
• No obvious driveability problems (may still run normally), though some CR-V owners report subtle idle or hesitation symptoms if EVAP issues are intermittent.
• Potentially reduced fuel economy if the ECM adapts to an EVAP fault.
• The EVAP system self-tests may fail during drive cycles or during an emissions inspection.

DIAGNOSTIC STEPS

Note: Always start with the simplest, lowest-cost checks and progress to more involved tests.

A. Initial verification

• Use an OBD-II scanner to confirm P0446 is current or in history; record any freeze-frame data (engine rpm, engine load, ignition status, fuel trim, etc.).
• Check for any related codes in the P04XX EVAP family (P0440–P0444, P0445, P0446, P0447, P0449, P0455, P0456, etc.). Document all codes present.

B. Visual and quick functional checks

• Gas cap: ensure it’s the correct part, seals properly, and is torqued to the recommended tightness after fueling. Replace if damaged or sticky.
• Inspect visible EVAP hoses and clamps for cracks, splits, or disconnections, especially near the vent valve and canister areas.
• Inspect connectors to the vent valve and purge valve for corrosion, dirt, or loose pins. Disconnect and reconnect if corrosion or oxidation is present; use contact cleaner as appropriate.

C. Electrical and circuit tests

• Vent valve (and associated wiring) test:
  • With engine off, locate the EVAP vent valve and inspect resistance across its terminals with a multimeter (per service data/specs). Compare to specification.
  • With ignition on (engine off) or during a running test, monitor the vent valve control circuit using an oscilloscope or scan tool to verify the PCM is energizing the valve when commanded.
  • Check for proper power supply and ground to the vent valve; verify there are no open circuits, shorts, or high resistance in the harness.
• If equipped, diagnose the purge valve circuit as a related check (test purge valve coil resistance and function; ensure the PCM is not causing a false reading on the vent circuit).

D. EVAP system integrity tests

• EVAP pressure test: Use a suitable EVAP pressure tester to pressurize the system and watch for drops in pressure that indicate leaks. Listen for hissing/leak sounds around hoses.
• Smoke test: A professional-grade smoke machine can reveal small leaks in hoses, canister, or valve seals that aren’t obvious visually.
• Canister and vent path check: If leaks are found in the canister or hoses, replace the faulty components and retest.

E. System operation and re-test

• After any component replacement (vent valve, hoses, clamps, canister, etc.), clear codes with the scan tool and run a full drive cycle to re-check the EVAP system tests.
• If the vent valve and wiring test OK and there are no leaks detected, but the code persists, consider PCM-related fault or software reprogramming/updates as a last resort (dealer-level diagnosis advised).

F. When you might consider professional help

• If you cannot locate a mechanical leak or a faulty vent valve with basic tests.
• If the diagnostic requires pressure/smoke testing or PCM reprogramming, or if multiple EVAP-related codes appear together.
• If you are uncomfortable with electrical diagnostics or using a pressure/ smoke test setup.

RELATED CODES

• EVAP family examples that may appear with or alongside P0446:
  • P0440 EVAP System Malfunction
  • P0441 Evaporative Emission System Incorrect Purge Flow
  • P0442 Evaporative Emission System Leak Detected (Small Leak)
  • P0443 Evaporative Emission Purge Valve Control Circuit
  • P0444 Evaporative Emission System Vapor Pressure Sensor
  • P0455 EVAP Large/Gross Leak
  • P0456 EVAP Small Leak
  • P0457 Evaporative Emission Vent Control Circuit Malfunction
• Note: Exact code availability and naming can vary by manufacturer and software level. Use the scan tool to view the exact codes stored in the vehicle’s PCM.

REPAIR OPTIONS AND COSTS (2025 prices)

Prices are ballpark ranges for typical U.S. market shops. Actual costs vary by region, shop rate, and parts choice (dealer vs. aftermarket).

• Gas cap replacement

  • Parts: $10–$40
  • Labor: $0–$20
  • Total: $10–$60

• EVAP vent valve replacement (often the most common fix for P0446)

  • Parts: $40–$180
  • Labor: 0.5–1.5 hours
  • Estimated total: $120–$500

• EVAP purge valve replacement (if diagnosed as related)

  • Parts: $40–$120
  • Labor: 0.4–1.0 hours
  • Estimated total: $100–$350

• EVAP hoses/clamps replacement (if leaks found)

  • Parts: $10–$60
  • Labor: 0.1–0.5 hours
  • Estimated total: $40–$200

• Charcoal canister replacement (rare; more involved)

  • Parts: $150–$600
  • Labor: 1–3 hours
  • Estimated total: $350–$1,200

• EVAP canister purge valve replacement (if separate from vent valve)

  • Parts: $30–$120
  • Labor: 0.5–1.5 hours
  • Estimated total: $100–$450

• PCM/ECU or wiring harness repair (rare; typically when no mechanical fault is found)

  • Parts: $200–$800 (additional ECU/repair costs can go higher)
  • Labor: 1–3 hours (repair or reprogramming)
  • Estimated total: $500–$2,000

• Note on costs: Prices shown are approximate 2025 figures. Labor times assume a standard shop environment and may be higher at specialty or dealer shops.

DIY VS PROFESSIONAL

• DIY-friendly tasks (if you are comfortable):
  • Inspecting and tightening/ replacing the gas cap.
  • Visual inspection of EVAP hoses, clamps, and accessible connectors.
  • Basic electrical checks on vent valve (when you have a suitable multimeter) and simple resistance checks if you have the vehicle’s specs.
  • Replacing a vent valve is often doable with basic hand tools if the valve is accessible from the engine bay or near the canister, but some layouts require under-car access or interior removal.
• Tasks typically better left to professionals:
  • Accurate EVAP pressure or smoke testing to locate leaks.
  • Diagnosing intermittent electrical faults with wiring harness faults or PCM control circuit issues.
  • Replacing the canister or performing a full EVAP system purge/vent valve diagnostic cycle with factory-level software or updates.
• Tools that help for DIY:
  • OBD-II scanner with EVAP test functions
  • Multimeter (to check resistance and continuity)
  • Vacuum/pressure test kit or EVAP smoke machine
  • Basic hand tools (screwdrivers, pliers, wrenches)
• Safety and warranty notes:
  • Evaporative system tests involve pressurized components; follow manufacturer service data.
  • Replacing certain components may affect warranty coverage; check with your dealer if under a factory warranty.

PREVENTION

• Regular checks and proactive maintenance:
  • Keep the fuel cap properly tightened and replace if worn or damaged.
  • Inspect EVAP hoses, clamps, and the canister area for cracks or deterioration during routine maintenance.
  • Address any fuel odors promptly; EVAP issues can worsen if leaks are ignored.
• Fuel and driving habits:
  • Use quality fuel and avoid extended periods with a nearly empty tank, which can cause more moisture and particulate issues in the EVAP system.
  • Occasional high-speed or spirited driving can help maintain pressure cycles, but rely on proper maintenance rather than “driving it out.”
• Post-repair cycle:
  • After any EVAP repair, perform a full drive cycle to allow the PCM to re-check the system; clear the check engine light only after confirming the fault is resolved.
• Professional maintenance:
  • If you’re near a smog/QA inspection, consider having an EVAP check performed by a technician prior to the test to avoid an emissions fail.

Bottom line

• P0446 on a 2017–2023 Honda CR-V points to an issue with the EVAP vent valve circuit, its wiring, or the valve itself. Start with the simplest checks (gas cap, hoses, connectors) and move toward electrical testing and a leak/pressure/smoke test as needed. Given the variability of EVAP layouts and the potential for related EVAP codes to appear, a methodical approach is key. If you’re not comfortable with electrical diagnostics or pressure testing, a professional technician is recommended. No recalls are listed in the provided NHTSA data for this scenario.