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EVAP System Malfunction

P0451, P0461 DETECTION CONDITION & POSSIBLE CAUSES

P0451, P0461

EVAP SYSTEM MALFUNCTION

DETECTION CONDITION

P0451 indicates the fuel tank pressure changes greater than 3.48 Kpa (14 in-H₂ O) in 0.10 seconds (sensor circuit noisy).
P0461 indicates the fuel level input noisy.

POSSIBLE CAUSE

Intermittent open or short in the FTP sensor circuit (P0451)
Intermittent open or short in the FLI circuit (P0461)

HINT

Fuel Tank Pressure Sensor Description

Used to measure the fuel tank pressure during the EVAP monitor test and to control excessive fuel tank pressure by forcing the system to purge.

Fuel Level Input Description

Indicates the fuel level in the tank.
Hard wire signal input to the powertrain control module (PCM) from the fuel pump (FP) module.

P0451, P0461 DIAGNOSTIC PROCEDURE

P0451, P0461		EVAP SYSTEM MALFUNCTION
STEP	INSPECTION		ACTION
1	PCM QUICK TEST Was the PCM quick test performed?	Yes	If any other DTG is present, Go to applicable DTC Troubleshooting. See DIAGNOSTIC TROUBLE CODE (DTC) INDEX - POWERTRAIN CONTROL MODULE (PCM) . If only DTC P0451 and/or P0461 are present, see GENERAL PINPOINT TEST 4: INTERMITTENT .
1	PCM QUICK TEST Was the PCM quick test performed?	No	Perform PCM quick test. See PCM QUICK TEST .