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Evaporative Emissions DTCS
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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
.