P1447 - FAULT CODE - OBD2

P1447 INFINITI, NISSAN: EVAPORATIVE EMISSION CONTROL SYSTEM PURGE FLOW MONITOR

The Evaporative Emission Control System (EVAP) has a purge flow that occurs under unsealed throttle conditions. This purge volume is closely related to the inlet air volume.

Under normal purge conditions, i.e., when the throttle is not closed, the EVAP purge volume control solenoid opens and thus allows flow. This flow exposes the EVAP system pressure sensor to the intake manifold vacuum.

The OBDII diagnostic code P1447 is set on the Infiniti or Nissan vehicles, which means the Purge Flow Monitor has detected a fault. The EVAP Pressure Sensor output voltage has shown a pressure drop and flows out of proper levels.

• Check Engine light ON.
• Decreased fuel efficiency.

The P1447 OBD2 fault code is set due to one of the following reasons:

• Possibly the EVAP purge volume control solenoid is stuck in the closed position or has bad wiring.
• The EVAP Pressure Sensor wires or connections may be damaged.
• The EVAP pressure sensor may be faulty.
• The EVAP connections may be improperly tightened or blocked.
• The Evaporative Emission Control System reservoir may have cracks in it.
• The Purge port may be clogged.
• The throttle position switch may be closed.

Steps to troubleshoot the OBDII DTC P1447:

• First, consult the Technical Service Bulletins.
• It is necessary to check if there are additional DTCs set with an automotive scanner, especially those that indicate specific EVAP problems.
• Check that the EVAP Purge Volume Control Solenoid circuit wiring and EVAP Pressure Sensor wiring are in optimal condition for proper operation. If you discover common damage from burns, corrosion, or wear, make appropriate repairs or replacements.
• Verify that the EVAP purge volume control solenoid valve is not stuck. If such a condition is found, make the necessary corrections.
• Measure the EVAP Pressure Sensor circuit voltages and check that they are within the parameters specified by the manufacturer. If you find out of range voltages, make the appropriate repairs.
• Check the EVAP hoses and tubing to verify that they are not blocked or deficient. Also, check the purge port for obstructions. Correct if necessary.