Did a tune-up points,cap,rotor,condenser,plugs,once running,no skip,pllenty of power,shut off,trouble starting.Pump gas,see plenty of gas going in,pull plug,compressed air comes out,plug dry, pump some more,starts up.Thinking pcv system not fuctioning properly causing a vapor lock of some sort,Pcv valve not stuck, but what is cannister below for, maybe clogged ?? Ty for any input.