2001 chev s-10 4.3 auto po 440

is there a way around the trip to the shop/smoke machine…[ can the system be bypassed or fooled in no more codes/engine light] there is a sensor in the system…?? where is it? since it drives fine and ive alrerady put a gas cap and silonoid valve into it but the light keeps coming back,this is why i want to disarm the issue.