P0440 Code: Honda CR-V (2017-2023) - Causes, Symptoms & Fixes

Here is a comprehensive diagnostic guide for OBD-II code P0440 (Evaporative Emission Control System Malfunction) as it may appear on a 2017–2023 Honda CR-V. Data from the NHTSA dataset provided shows no recalls or official complaints for this specific issue and model-year combination. No recalls found in NHTSA database. Because the dataset has no complaint counts, I cannot provide prevalence statistics; this guide uses general automotive knowledge to help you diagnose and repair P0440 on these CR-Vs.

CODE MEANING AND SEVERITY

• What P0440 means: P0440 is the generic OBD-II code for Evaporative Emission (EVAP) System Malfunction. It indicates the vehicle’s computer detected an abnormal condition in the EVAP system, which is designed to capture and store fuel vapors from the fuel system and release them to the engine for combustion under controlled conditions.
• Severity: Moderate. The MIL (Check Engine Light) will usually illuminate, and the vehicle may fail an emissions test. Driveability is typically not affected, but a leak or persistent fault can lead to poor emissions performance and increased evaporative emissions if not addressed.
• What it does not always imply: A missing or loose gas cap can trigger EVAP codes, but P0440 is a general failure code. The root cause could be a small leak, a faulty valve, a canister issue, wiring problems, or a combination of components in the EVAP system.

COMMON CAUSES ON HONDA CR-V

The CR-V EVAP system consists of the canister (charcoal storage), purge valve (solenoid), vent valve (or vent control), hoses, the filler neck, a pressure/venturi sensor, and associated wiring. In practice, P0440 on Honda CR-Vs is commonly caused by:

• Loose, damaged, or cracked gas cap (or a non-OEM cap). Although more often linked to P0442 or P0455/0456, a failing gas cap can contribute to an EVAP fault condition.
• Damaged, cracked, or split EVAP hoses and vacuum lines, especially near the canister, purge valve, or vent valve.
• Faulty EVAP purge valve (MM or purge solenoid) or failed vent valve, leading to incorrect purge or vent behavior.
• Leaks or restrictions in the EVAP canister (charcoal canister) or canister vent line.
• Fuel filler neck or surrounding fuel system area with leaks or damage.
• Electrical issues: faulty purge/vent valve electrical connectors, wiring harness wear, blown fuse, or PCM/ECU communication problems related to the EVAP circuit.
• Leak Detection Pump (LDP) or pressure-sensing issues (if equipped on your trim) or related sensors/wiring.
• Accumulated contaminants or a degraded EVAP system due to age, road grime, or exposure to fuel spills affecting seals and joints.

SYMPTOMS

• Check Engine Light (MIL) on or flashing.
• Emissions readiness may fail; may fail an initial emissions test.
• Possible fuel odor near the vehicle if a larger EVAP leak is present.
• Generally no noticeable loss of power or drivability, though some drivers may report slight roughness if other related codes appear.
• In rare cases, the EVAP fault may be associated with a purge-related drivability concern if the purge valve is stuck open/closed during specific RPM/loads.

DIAGNOSTIC STEPS

Perform a methodical inspection and testing sequence. Use a good OBD-II scanner to read codes and freeze frame data, and note any related codes (P0441, P0442, P0443, P0444, P0445, P0446, etc.).

A. Confirm and document

• Read all stored and pending codes with a capable scanner.
• Note freeze-frame data: engine load, RPM, vehicle speed, fuel trim, EVAP status.
• Confirm the P0440 is present and whether any related EVAP codes accompany it.

B. Visual inspection first

• Gas cap: ensure it is present, undamaged, and properly torqued. If it’s old or damaged, replace with a quality cap (OEM or equivalent) and clear codes after a drive.
• EVAP hoses and connections: inspect for cracks, splits, wear, rubbing, loose clamps, or disconnections, particularly around the canister, purge valve, vent valve, and filler neck.
• Filler neck and surrounding area for leaks or spills.
• Canister exterior for signs of damage or moisture around hoses.

C. Quick functional checks

• Purge valve (solenoid): with engine off, you can sometimes test by commanding purge on/off with an appropriate scan tool. Listen for an audible click from the purge valve when commanded; if no click or it sounds stuck, it may be defective.
• Vent valve: similar logic as purge valve; verify electrical connection and function if you have the tool capability.

D. Pressure and leak testing

• Perform a EVAP system leak check: a smoke test is the most definitive method; it reveals vacuum leaks, cracked hoses, bad canister, or faulty valves. If you don’t have access to a smoke machine, a professional shop can perform this.
• If you have the equipment, perform a vacuum/pressure test on the EVAP system using a dedicated EVAP test kit or a hand-held vacuum pump and a pressure gauge. Compare readings to specifications (watch for gradual drop in pressure indicating a leak).

E. Inspect the EVAP canister and lines

• Look for signs of canister damage or degradation; a compromised canister often causes leaks or restricted flow.
• Inspect the purge and vent valve seal surfaces and gaskets for wear.
• Check associated wiring and connectors for corrosion, melted insulation, or looseness.

F. Advanced diagnostics (if needed)

• Use the scan tool’s EVAP test function to run a self-test sequence: purge valve commanded open/closed, monitoring system pressure and leaks.
• If the LDP (Leak Detection Pump) is present, test its operation and wiring.
• If no leak is found but the code persists, speculatively replace the suspected component (most commonly the purge valve or vent valve) and recheck.

G. Post-repair verification

• After any repair, clear codes and drive the vehicle through typical operating temperatures and loads to ensure the EVAP monitor completes and a “pass” status is achieved on the EVAP readiness monitors.
• If a leak test was performed, re-run the smoke test to confirm no leaks remain.

RELATED CODES

• Other EVAP-related codes you might encounter with P0440 in the CR-V family include:
  • P0441: EVAP System Incorrect Purge Flow
  • P0442: Evaporative Emission System Small Leak Detected
  • P0443: Purge Control Valve Circuit
  • P0444: Purge System Fault
  • P0445: Evaporative Emission System Purge Valve Circuit
  • P0446: Evaporative Emission System Vent Control Circuit
  • P0455: Evaporative Emission System Large Leak Detected
  • P0456: Evaporative Emission System Very Small Leak Detected
• Note: The exact subcodes may vary slightly by scanner and vehicle year; the EVAP family codes are often interrelated, and fixing one issue may resolve others.

REPAIR OPTIONS AND COSTS (2025 PRICES)

Prices vary by region, shop, and whether you do it yourself. The ranges below reflect typical parts and labor in 2025 dollars for a CR-V (2017–2023). Labor times are approximate and can vary.

• Gas cap replacement

  • Parts: $10–$40
  • Labor: $0–$40 (if DIY at home; typical shop minimum)
  • Typical total: $15–$80
  • Notes: Often resolves P0440 if the cap was the actual source of the leak or vent condition.

• EVAP purge valve replacement

  • Parts: $60–$180
  • Labor: $60–$150
  • Typical total: $120–$330
  • Notes: A common fix for P0440 if purge flow is incorrect or valve is stuck.

• EVAP vent valve replacement

  • Parts: $50–$150
  • Labor: $80–$180
  • Typical total: $130–$330
  • Notes: If vent valve is stuck or leaking, this often resolves the fault.

• Charcoal canister (EVAP canister) replacement

  • Parts: $150–$600
  • Labor: $150–$500
  • Typical total: $300–$1100
  • Notes: More expensive; canister failure or large leaks may require replacement.

• EVAP leak detection pump (LDP) or related ECU wiring (if applicable)

  • Parts: $100–$350
  • Labor: $100–$250
  • Typical total: $200–$600
  • Notes: Not all trims use a separate LDP; many CR-Vs use valve-based diagnostics.

• EVAP system hoses, clamps, and fittings

  • Parts: $5–$100 (depending on hose length and complexity)
  • Labor: $80–$180
  • Typical total: $85–$280
  • Notes: Common and relatively inexpensive if leaks are found in hoses or clamps.

• Smoke test service (diagnostic only)

  • Parts: N/A
  • Labor: $80–$150
  • Typical total: $80–$150
  • Notes: Highly effective for locating leaks; many shops include this in the diagnostic fee.

• Fuel filler neck or related line repair

  • Parts: $20–$150
  • Labor: $80–$200
  • Typical total: $100–$350
  • Notes: Leaks here can trigger P0440.

• Miscellaneous electrical repair (wiring, connectors)

  • Parts: $5–$100
  • Labor: $80–$200
  • Typical total: $85–$300

DIY vs PROFESSIONAL

• DIY suitable for:
  • Replacing a faulty gas cap.
  • Replacing easily accessible hoses or clamps with careful inspection.
  • Clearing codes after a simple fix and verifying the EVAP monitor completes (requires a decent OBD-II scanner).
  • Basic purge valve replacement if the valve is easy to access and you’re comfortable with the electrical connector and vacuum lines.
• Professional required or strongly recommended for:
  • Diagnosing hard EVAP leaks with smoke testing or specialized equipment.
  • Replacing the charcoal canister or vent/purge valves that require removing components or accessing hard-to-reach areas.
  • Diagnosing and repairing wiring harness faults, pressure sensors, or leak detection pump (if present).
  • If monitor readiness or emissions testing requires formal verification, or if multiple EVAP codes appear.

PREVENTION

• Use a good, properly rated gas cap; replace if cracked, warped, or missing.
• Always tighten the gas cap until it clicks; avoid overtightening.
• Address any fuel spills immediately; wipe clean and allow time for the area to dry to prevent contamination of seals.
• Periodically inspect EVAP hoses, clamps, and the filler neck for wear, cracks, or looseness; replace as needed.
• Use quality fuel and avoid frequent fuel spills during refueling; consider standard maintenance intervals for EVAP components as recommended by Honda.
• If you notice a gas odor or the MIL comes on frequently, don’t ignore it; early diagnostics can prevent more expensive repairs.
• If your CR-V is due for an EVAP service or shows readiness monitor issues, have the EVAP system inspected as part of routine maintenance.

Data limitations

• The provided dataset shows no recalls for this make/model/year/issue in NHTSA, so I cannot cite any recalls or related TSBs here. No recalls found in NHTSA database.
• There are no user complaint counts available in the provided data to establish prevalence or typical failure rates for P0440 on 2017–2023 CR-V. The diagnostic steps and repair cost estimates above reflect general EVAP knowledge and typical repair practice rather than dataset-derived statistics.

If you’d like, I can tailor the diagnostic steps to your exact symptoms (e.g., whether there’s an odor, the exact EVAP-related codes reported, or whether the purge/vent valves are accessible in your trim) and provide a more specific parts list and timing for your local area.