GMC 1997277 Valve,Evap Emission Canister Purge Solenoid

The Evaporative Emissions Control System (EVAP) work by confining fuel vapor inside the fuel system hence keeping it from escaping into the atmospher in a similar manner to the PCV system, but trapping the vapors inside the fuel tank until the pressure reaches a level that unseats the pressure relief valve wherein the vapors are redirected to a carbon canister for a brief time. When specific engine parameters are met vacuum from the manifold opens purge control valve to result into allowing the vapors to be drawn into the intake manifold for combustion. Three methods control this process: a ported vacuum source through the Thermo Vacuum Switch (TVS), manifold vacuum accompanied by an EVAP purge control valve, and an EVAP Purge Control Solenoid of the later models. The carbon canister is located at the different positions depending on the model year of your vehicle, if your vehicle model is before 2000 it is located in the engine compartment and if it is after 2000 it is placed underneath the car. Signs of EVAP system failures include fuel smell or a raw fuel leakage with prominence during hot weather. From 1996, models are equipped with a fuel tank pressure sensor that checks the leakage of vapor and sets a trouble code and the SERVICE ENGINE SOON lamp, typically due to a poorly tightened gas cap. The fuel filler cap is incorporated with a safety feature that is the two-way pressure-vacuum relief valve. To do this self-test the vacuum and vapor hoses should be checked for signs of wear and tear, the carbon canister should be examined and the gas cap seal should be examined. These tests include determining the presence of vacuum at three temperatures for the TVS and EVAP purge control solenoid. The vacuum-operated purge control valve should open very little when no vacuum is applied to it and quite a lot when vacuum is applied to it. Component replacement is performed at the TVS, solenoid, and carbon canister, and disconnecting/reconnecting with attention paid to the condition of seals; filters must be clean for particular components.

The EVAP system works by letting its charcoal-filled tank take fuel vapors from the tank, then letting the engine pull those vapors into its intake during operation. The EVAP system works when different parts come together: the activated charcoal canister, purge valve, vent valve, pressure sensor, fuel tank, and air release and fuel line connections. The vapor from fuel tank passes through a check valve and vapor tube before going into the charcoal canister, where the activated charcoal holds and traps the vapors. The ECM/PCM makes vapors more available by opening certain valves in certain conditions. The computer control unit controls how vapor passes through by repeatedly switching on the EVAP purge valve solenoid throughout each second according to engine conditions. These newer models use OBD-II technology to test for gas leaks in two ways: by drawing a vacuum on the canister system, and by checking fuel tank pressure to find where liquid is escaping. Just like the MAP sensor, this fuel tank pressure sensor sends a voltage signal to the PCM to help measure the pressure of air inside the tank. The Federal government guarantees the warranty for the evaporative control system, but most problems start from disconnected or damaged hoses that can be easily checked. When there is no electronic purge control like early models had, you need to examine the charcoal canister along with its components for harm or signs it was incorrectly routed. Late models need someone to examine both fuses and the electrical wiring of these two valves, which stay off unless they're turned on by the Engine Control Module. To fix parts that break on the EVAP canister, you need to clean the connection area before taking it apart, and you must follow separate guidelines depending on which year your car was made.

The EVAP system works by letting its charcoal-filled tank take fuel vapors from the tank, then letting the engine pull those vapors into its intake during operation. The EVAP system works when different parts come together: the activated charcoal canister, purge valve, vent valve, pressure sensor, fuel tank, and air release and fuel line connections. The vapor from fuel tank passes through a check valve and vapor tube before going into the charcoal canister, where the activated charcoal holds and traps the vapors. The ECM/PCM makes vapors more available by opening certain valves in certain conditions. The computer control unit controls how vapor passes through by repeatedly switching on the EVAP purge valve solenoid throughout each second according to engine conditions. These newer models use OBD-II technology to test for gas leaks in two ways: by drawing a vacuum on the canister system, and by checking fuel tank pressure to find where liquid is escaping. Just like the MAP sensor, this fuel tank pressure sensor sends a voltage signal to the PCM to help measure the pressure of air inside the tank. The Federal government guarantees the warranty for the evaporative control system, but most problems start from disconnected or damaged hoses that can be easily checked. When there is no electronic purge control like early models had, you need to examine the charcoal canister along with its components for harm or signs it was incorrectly routed. Late models need someone to examine both fuses and the electrical wiring of these two valves, which stay off unless they're turned on by the Engine Control Module. To fix parts that break on the EVAP canister, you need to clean the connection area before taking it apart, and you must follow separate guidelines depending on which year your car was made.

When conditions are right, the Powertrain Control Module (PCM) opens the canister purge solenoid, allowing vapors to be drawn into the intake manifold and consumed by the engine.

To remove the EVAP canister vent solenoid, start by disconnecting the electrical connector and quick-connect fittings from the solenoid. Then, remove it from its mounting bracket.

To remove the EVAP canister vent solenoid, start by disconnecting the electrical connector and quick-connect fittings from the solenoid. Then, remove it from its mounting bracket.