P1440
EVAP Emission Control System — Purge Valve Stuck Open
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The P1440 is a Ford-specific code indicating that the EVAP (Evaporative Emission Control) system's purge valve is stuck in the open position. The EVAP system captures fuel vapors from the gas tank and routes them to the engine to be burned rather than released into the atmosphere. The purge valve controls when these vapors enter the intake manifold — it should only open under specific engine conditions.
When the purge valve is stuck open, fuel vapors continuously flow into the intake manifold, which can cause a rough idle (especially when cold), a slight fuel smell, and minor drivability issues. The engine may run richer than normal because the extra fuel vapors upset the air-fuel ratio. While not immediately dangerous, this condition should be addressed as it can affect emissions and fuel economy.
The purge valve is typically located on or near the intake manifold and is one of the easier EVAP components to replace. It's an inexpensive part ($20–$50) and usually held in place by a single bolt or clip with two hose connections and an electrical connector. This is a straightforward DIY repair for most Ford vehicles. After replacement, clear the code and drive through a couple of EVAP monitor cycles to confirm the fix.
Severity
Symptoms
- •Check engine light is on
- •Faint fuel smell around the vehicle
- •Rough idle, especially when cold
- •Slightly reduced fuel economy
- •Vehicle may fail emissions testing
Likely Causes
The EVAP purge valve is mechanically or electrically stuck in the open position, allowing fuel vapors to flow into the intake manifold at inappropriate times.
Damaged wiring or a short in the purge valve circuit can keep the solenoid energized and open when it should be closed.
Deteriorated rubber hoses in the EVAP system can allow unmetered fuel vapors to enter the intake, mimicking a stuck-open purge valve.
The PCM's internal circuit that controls the purge valve may have a fault keeping the valve in the open state.
Estimated Cost
Professional Repair
Includes parts + labor
Common Fixes
- Replace the EVAP canister purge valve (solenoid)
- Inspect and replace cracked or deteriorated EVAP hoses
- Check and repair wiring to the purge valve
- Clear the code and verify the repair with an EVAP system test