Durango 4WD V8-5.9L VIN Z (1998)
Canister Purge Solenoid: Description and Operation
Duty Cycle EVAP Purge Solenoid
PURPOSE
The solenoid regulates the rate of vapor flow from the EVAP canister to the intake manifold.
OPERATION
A duty cycle EVAP canister purge solenoid is used. The PCM operates the solenoid.
During the cold start warm-up period and the hot start time delay, the PCM does not energize the solenoid. When de-energized, no vapors are
purged. The PCM de-energizes the solenoid during open loop operation.
The engine enters closed loop operation after it reaches a specified temperature and the time delay ends. During closed loop operation, the PCM
cycles (energizes and de-energizes) the solenoid 5 or 10 times per second, depending upon operating conditions. The PCM varies the vapor flow
rate by changing solenoid pulse width. Pulse width is the amount of time that the solenoid is energized. The PCM adjusts solenoid pulse width
based on engine operating condition.
CIRCUIT OPERATION
The Powertrain Control Module (PCM) operates the EVAP/Purge solenoid by providing a ground path on circuit K52. Circuit K52 connects to
PCM cavity C20. Circuit A21 supplies battery voltage to the EVAP/Purge solenoid.
