P0440low severityPowertrain
Evaporative Emission Control System Malfunction
on 2011 Lincoln MKX 3.7L V6 · AWD
What this code means
General EVAP system malfunction. The EVAP system captures fuel vapors and prevents them from escaping to the atmosphere.
Symptoms
- Check Engine Light
- Fuel smell
- Failed emissions test
Common causes
- Loose or missing gas cap (most common)
- Cracked EVAP hose
- Faulty purge valve
- Faulty vent valve
- Charcoal canister saturated
- Leak in fuel tank or filler neck
Diagnostic steps
- Check gas cap seal and tighten
- Perform EVAP smoke test
- Test purge valve
- Test vent valve
- Check EVAP hoses
- Inspect charcoal canister
Repair notes
Start with gas cap - tighten and clear code. If returns, smoke test the EVAP system.
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1