1995 Chevy Blazer Evaporative emission control system

no it's not ruined. when you go over 30 it sucks it back into the engine or puts it in the tank. your purge vavle is probably shot though....

How would I know if the purge valve is shot and why is there gas in the vapor canister? When I fill the tank up I do not top it off.

this is the proper terminology for it. your valve is shot because the orfice is opening to much and sucking fuel into the cannister.........





In an evaporative emission control system of an internal combustion engine wherein volatile fuel that has evaporated from a liquid fuel tank is collected in a collectioncanister that, under certain engine operating conditions detected by an electronic control system of the engine, is purged to the engine by a purge regulator under the control of said electronic control system so as to cause collected fuel vapors to becombusted by the engine, the improvement which comprises a variable orifice that conjointly with said purge regulator exercises control over the vapor flow from said canister to the engine and functions to selectively restrict vapor flow from thecanister to the engine in correlation with the degree to which the engine is being throttled, and a sensor for supplying the electronic control system with a signal indicative of the degree to which the engine is being throttled and hence also the degreeof restriction imposed by said variable orifice on the flow from the canister to the engine so that the electronic control system can take the degree of restriction imposed by said variable orifice into account in setting the purge regulator.