2004 low engine vacuum and poor milage

running constant 13" of vacuum. poor milage. can not find vacuum leak anywhere. no drivability issues besides milage. new plugs, wires, PVC, air filter, fuel filter. cleaned MAF and TB. Codes have been cleared but were P0171 bank 1 lean (Twice) and P0455 grosse evap leak. 171,000 hard miles

Start spraying starter fluid around all the vacuum lines and gaskets etc. When the rpm jumps you found your leak.