K 2500 Suburban 4WD V8-454 7.4L VIN N TBI (1995)
Evaporative Emission Control Canister: Description and Operation
OPERATION
Fuel vapors from the fuel tank are purged and flow into the vapor canister tube labeled 'tank" and are absorbed by the carbon. The canister is
purged when the engine is able to use the extra fuel vapor A vacuum source is applied to the vapor canister tube labeled "purge" to draw fresh air
through the top of the canister. The air mixes with the fuel vapor and the mixture is drawn into the intake manifold to be consumed in the normal
combustion process.
While the canister is purging, fresh air is drawn in through the air inlet at the top of the canister. Air flows to the bottom of the canister and forces
the vapors out the "purge" tube.
