'04 5.7l has small evap leak. I made a smoke machine, but need attach advise, to check canister vent vave, propotional vent valve, purge valve, gas cap, gas tank top connections and hose routings. Need locations, and best approach. Smoke will show my problem. The truck runs rough and idles low, about two hundred. I am replaceing #7 injector, then will move on to smokin the evap system. Just need some advise.