P0440low severityPowertrain
Evaporative Emission Control System Malfunction
on 2001 Subaru Legacy 2.5L SOHC EJ251/EJ253 Flat-4 (165 hp) ยท 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
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0010
Intake Camshaft Position Actuator Circuit/Open Bank 1
P0011
Intake Camshaft Position Timing Over-Advanced Bank 1
P0012
Intake Camshaft Position Timing Over-Retarded Bank 1
P0013
Exhaust Camshaft Position Actuator Circuit/Open Bank 1
P0014
Exhaust Camshaft Position Timing Over-Advanced Bank 1
P0015
Exhaust Camshaft Position Timing Over-Retarded Bank 1