Evaporative Emission Control System Malfunction
2016-2018 Lincoln MKX 3.7L V6
Description
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.
Related Codes
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
P0440 on Other Vehicles
Lincoln Aviator
2003-2005 4.6L V8
Lincoln Aviator
2003-2005 4.6L V8 DOHC
Lincoln Aviator
2020-2024 3.0L Twin-Turbo V6
Lincoln Aviator
2020-2024 3.0L V6 Twin Turbo
Lincoln Aviator Grand Touring
2020-2024 3.0L Twin Turbo V6 PHEV
Lincoln Aviator Grand Touring
2020-2024 3.0L Twin-Turbo V6 Hybrid
Lincoln Aviator Grand Touring
2020-2024 3.0L V6 Twin Turbo Hybrid
Lincoln Blackwood
2002-2002 5.4L V8
Common Questions
What does code P0440 mean on a 2016-2018 Lincoln MKX?
P0440 stands for "Evaporative Emission Control System Malfunction". General EVAP system malfunction. The EVAP system captures fuel vapors and prevents them from escaping to the atmosphere.
What are the symptoms of P0440 on a Lincoln MKX?
Common symptoms of P0440 include: Check Engine Light, Fuel smell, Failed emissions test.
What causes P0440 on a 2016-2018 Lincoln MKX?
Common causes of P0440 include: 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.