System Description

This diagnostic monitors the evaporative emission (EVAP) system for the correct operation of the purge solenoid. The control module seals the EVAP system by commanding the EVAP canister purge valve Closed and the EVAP canister vent valve Closed. The control module monitors the fuel tank pressure (FTP) sensor in order to determine if a vacuum is being drawn on the EVAP system. If vacuum in the EVAP system is more than a predetermined value within a predetermined time, this DTC sets.

The following table illustrates the relationship between the ON and OFF states, and the Open or Closed states of the EVAP canister purge and vent valves.