P0446 2004 GMC Sierra 1500 5.3 liter what could still cause the evap system to trigger the light

Question

actual code is po446a , vent valve solenoid, purge valve, and charcoal canister have been
replaced. have not found any bends are holes in vent hoses

Answer 1

Hi there,

Make sure the hoses are clear, if they are, replace the pressure sensor because its not reading properly.