Circuit Description
The fuel tank pressure sensor measures the pressure changes within the EVAP
system. The sensor signal is monitored for rationality as well as electronic functionality.
The rationality diagnostic is only performed at idle after a cold start. In this case,
the pressure will be monitored. If the pressure exceeds 250 kPa for longer
than 3 seconds, the ECM will set this code.
DTC Parameters
DTC P0451 will set if fuel tank pressure sensor value is greater than 250 kPa
when:
| • | Condition exists for longer than 3 seconds |
| • | Engine coolant temperature at start less than 33°C (91°F) |
| • | Engine running less than 10 seconds |
P0451 is a (type B) DTC.
Diagnostic Aids
Possible causes:
| • | Skewed or stuck fuel tank pressure sensor |
| • | Intermittent open in signal circuit |
| • | Intermittent open in return circuit |
