Detection Condition
WARNING: This page is about a different car, the 2002 Mazda Tribute. However, it is still accessible from the selected car via links, so may be relevant.
DTC P0451 indicates fuel tank pressure changes more than 14 in. H2 O in 0.10 seconds (sensor circuit noisy).
DTC P0461 indicates fuel level input noisy.
Fuel Tank Pressure (FTP) sensor measures fuel tank pressure during EVAP monitor test and to control excessive fuel tank pressure by forcing a system purge. Fuel level input indicates fuel level in tank with a hard wire signal input to PCM from fuel pump module.