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Home >> Jeep >> 2008 >> Liberty Limited, 4WD, Part Time >> Repair and Diagnosis >> Engine Performance >> System >> DTCS P0420 To P0563 >> P0440-General EVAP System Failure >> Possible Causes
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Possible Causes

Possible Causes 
EVAP PURGE SOLENOID VACUUM SUPPLY
EVAP PURGE HOSE/TUBE AND FRESH AIR FILTER OBSTRUCTION
(Z913) GROUND CIRCUIT OPEN
(K107) ESM SIGNAL CIRCUIT OPEN
EVAPORATIVE EMISSION LEAK
EVAP SYSTEM MONITOR SWITCH
EVAP PURGE SOLENOID
POWERTRAIN CONTROL MODULE (PCM)

Always perform the PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.