Oldsmobile 17113148 Canister,Evap Emission

Various modifications were made to reduce escaping gasoline vapours; they include redesigned bowl vents, low bowl capacity, heat shields, and better insulation between intake manifolds and carburettors. This should eliminate the release of fuel tank vapors into the atmosphere through a carbon canister storage which holds in its storage activated carbon device which collects the vapors produced from the engine induction system every time the engine is off. When operating some of the stored fuel vapors are expelled by the intake air and burnt normally. The 231 V6 engine introduced in 1981 has an electronically controlled purge function through a solenoid connected to the Electronic Control Module (ECM) managing vacuum to the purge valve depending on the system mode. Earlier carbon canisters are generally open that sucks in air from the bottom of the canister but some of the newer models have got the closed canister system that draws its air from the air cleaner. Service entails from time to time replacing the canister filter if any, or any replacement fuel tank cap to its original type. For canister removal, hoses are disconnected, retainer screws are turned back, and the canister is lifted off the car; if the car is equipped with A/C, additional exposure buttons are loosened as well. The canister is then labeled and disconnected for use; installation, on the other hand, is done in the following order. To replace the filter, the vapor canister is taken off, then the filter is pulled out from the bottom and a replace it with a new one then the canister is replaced.

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.

This system is designed to trap and store fuel vapors that evaporate from the fuel tank, throttle body, and intake manifold. It consists of a charcoal-filled canister and the lines connecting the canister to the fuel tank, ported vacuum, and intake manifold vacuum. Fuel vapors are transferred from various components to the canister where they are stored when the engine is not operating. When the engine is running, the fuel vapors are purged from the canister by intake air flow and consumed in the normal combustion process. The ECM operates a solenoid valve to control vacuum to the purge valve in the canister. Under certain conditions, the solenoid is turned on to close the valve and block vacuum to the canister purge valve. The solenoid is turned off to allow purge when the engine is warm and meets specific criteria. The control valve prevents purge to the intake manifold under low vacuum conditions. If the solenoid is open or not receiving power, the canister can purge to the intake manifold at all times, causing rough idle or rich operation. Inoperative purge valve, damaged canister, split or cracked hoses, or incorrect hose connections can result in poor idle, stalling, and poor driveability. Evidence of fuel loss or odor can indicate issues such as fuel leaks, damaged canister, inoperative valves, or faulty hoses. Inspecting and repairing or replacing hoses, canister, and components as necessary is recommended. Component replacement instructions for the fuel vapor canister solenoid and canister are provided.

The Evaporative Canister is designed to limit gasoline vapor discharge into the air when the vehicle is not operating.