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Evaporative Emissions DTCS

EVAPORATIVE EMISSIONS DIAGNOSTICS TROUBLE CODE (DTC) LIST

DTC Description Source Perform Test
P0442 Small leak detected in EVAP system (As small as 1.02 mm [0.040 inch]) PCM Go To PINPOINT TEST A: DTC P0442 SMALL LEAK IN EVAP SYSTEM, DTC P0456 VERY SMALL LEAK IN EVAP SYSTEM, DTC P0457 CHECK FOR MISSING OR LEAKING FUEL FILLER CAP .
P0455 Major leak or no flow detected PCM Go To PINPOINT TEST B: DTC P0455 MAJOR LEAK OR NO FLOW DETECTED OR DTC P1443 VERY SMALL OR NO PURGE FLOW DETECTED IN SYSTEM .
P0456
  • Very small holes or cuts in fuel vapor hoses/tubes.
  • Loose fuel vapor hose/tube connections to EVAP system components.
  • EVAP system component seals leaking.
PCM Go To PINPOINT TEST A: DTC P0442 SMALL LEAK IN EVAP SYSTEM, DTC P0456 VERY SMALL LEAK IN EVAP SYSTEM, DTC P0457 CHECK FOR MISSING OR LEAKING FUEL FILLER CAP .
P0457 Check for missing or leaking fuel filter cap PCM Go To PINPOINT TEST A: DTC P0442 SMALL LEAK IN EVAP SYSTEM, DTC P0456 VERY SMALL LEAK IN EVAP SYSTEM, DTC P0457 CHECK FOR MISSING OR LEAKING FUEL FILLER CAP .
P1443 Very small or no purge flow detected PCM Go To PINPOINT TEST B: DTC P0455 MAJOR LEAK OR NO FLOW DETECTED OR DTC P1443 VERY SMALL OR NO PURGE FLOW DETECTED IN SYSTEM .
P1450 Excessive vacuum detected in the fuel tank PCM Go To PINPOINT TEST C: DTC P1450 EXCESSIVE VACUUM DETECTED IN THE FUEL TANK .