I just got my truck the former owner told me there was a issue with the Evap, and that he recently changed the gas cap. I had the truck E-checked, which they check the fuel nozzle and gas cap everything passed, 200 miles later I have these two lights come up.
P0442 Evap. emissions control leak (small)
P0455 Evap. Emissions Control Leak (large)
My engine is a 4.7L V8, where should I start my search to fix it?