Recently my truck has been sitting a lot more than normal and the other day i jumped in it to head to a buddys house when the check engine light came on. P0300 random and multiple misfires. as well as p0455 large evap leak. well ive tried everyhting i can think of and still no luck fixing this problem. Runs righ at idle and as soo as you rev up engine like starts flashing. Any help would be appreciated

 

Do a crank relearn with a diagnostic tool should fix the p0300 takes 2 minutes. P0455 could be your gas cap