I have a 2003 Nissan with a code of P1456 canister was loose and gas cap was bad still showing that codeany suggestion
evap system code p1456 small leak 0.020" the canister was loose and replaced the gas cap any other places to look
Begin by clearing the code with a code reader or unplug the battery during the night. If it comes back, you may need to replace the evap switch. This is a known issue on these cars. The replacement part is more robust than the factory one. Be aware that the evap switch costs between 100$ and 200$.
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