P0455 :Major leak in purge system, hose in system not connected or, cap open/leaking.

Need to do a visual check of EVAP components.
Did you have the code cleared with a scan tool?

Do NOT apply 4 to 5 psi to the system, you will rupture a line fitting or worse distort the fuel tank....system uses about 1/2psi ( Half.) negative to self check.

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