Description - Evaporation Control System

WARNING: This page is about a different car, the 2005 Jeep Liberty. However, it is still accessible from the selected car via links, so may be relevant.

The evaporation control system prevents the emission of fuel tank vapors into the atmosphere. When fuel evaporates in the fuel tank, the vapors pass through the control valve located in the top section of the fuel pump module, through the fuel management valve, and through vent hoses and tubes to a charcoal filled evaporative canister. The canister temporarily holds the vapors. The Powertrain Control Module (PCM) allows intake manifold vacuum to draw vapors into the combustion chambers during certain operating conditions.

Gas powered engines use a duty cycle purge system. The PCM controls vapor flow by operating the duty cycle EVAP purge solenoid. Refer to EVAP/PURGE SOLENOID .

When equipped with certain emissions packages, a Leak Detection Pump (LDP) will be used as part of the evaporative system for OBD II requirements. Also refer to PUMP-NATURAL VAC LEAK DETECTION .

Vehicles powered with gasoline engines are also equipped with ORVR (On-Board Refueling Vapor Recovery). Refer to ORVR for additional information.

NOTE: The evaporative system uses specially manufactured lines/hoses. If replacement becomes necessary, only use fuel resistant, low permeation hose.

Certain components can be found in Fig 1.

Fig 1: Fuel Delivery Components

Courtesy of DAIMLERCHRYSLER CORP.

1 - FUEL TANK	10 - EVAP CANISTER
2 - FUEL TANK STRAPS	11 - FLOW MANAGEMENT VALVE
3 - FUEL PUMP MODULE LOCK RING	12 - FRESH AIR TUBE
4 - CHECK (CONTROL) VALVE	13 - HOSE SLEEVE
5 - FUEL PUMP MODULE FLANGE	14 - FUEL FILTER
6 - FUEL FILL HOSE	15 - LEAK DETECTION PUMP
7 - FRESH AIR FILTER	16 - HEAT SHIELD
8 - FUEL FILL CAP/BEZEL	17 - SKID PLATE
9 - FUEL FILL TUBE