Dodge Durango

 Service Manual

Emission Control Systems » Evaporative emission controls » Description and operation
Duty cycle evap canister purge solenoid

OPERATION

The duty cycle EVAP canister purge solenoid (DCP) regulates the rate of vapor flow from the EVAP canister to the intake manifold. The Powertrain Control Module (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.

Evaporation control system

Rollover valve

Evaporation (evap) canister

Duty cycle evap canister purge solenoid

Leak detection pump (ldp)

Positive crankcase ventilation (pcv) system

Positive crankcase ventilation (pcv) system-4.7L engine

Vehicle emission control information (veci) label