P0440 means evaporative emission control system malfunction. General fault in the EVAP system, which traps fuel vapors so they don't escape into the air. Usually a leak, a bad valve
You can keep driving — get it checked when convenient.
General fault in the EVAP system, which traps fuel vapors so they don't escape into the air. Usually a leak, a bad valve, or — very commonly — a loose gas cap.
Check this first — it's free.
Cracked with age.
Stuck open or closed.
Can't seal the system.
Cracked housing.
Typically $0–$400
Gas cap check is free; purge/vent valve typically $150–$400. Estimates vary by vehicle. Costs are estimates and vary by vehicle, location, and shop.
Safe to drive — this is an emissions/vapor issue, not a breakdown risk. Tighten the gas cap and see if the light clears after a few drive cycles.
Typically $0–$400. Gas cap check is free; purge/vent valve typically $150–$400. Estimates vary by vehicle.
You can keep driving — get it checked when convenient.
The most common cause is loose or faulty gas cap. Check this first — it's free.