AI4Car quick readA short, original guide from the AI4Car knowledge library.
P0455 is an evaporative-emissions large-leak code. Make sure the cap is fitted correctly and inspect its seal if your vehicle uses one. Some cars have capless filler systems, so follow the owner's instructions.
If the code returns, the leak may be elsewhere in the EVAP plumbing, valve, or tank area. A smoke test and the correct service procedure are more useful than replacing parts based on the code alone.
Quick educational note
For information, not a diagnosis or repair instruction. Vehicle-specific checks are still required. Consult the manufacturer's guidance and a qualified technician.
How to use this information
This article explains general principles and does not establish what is wrong with your vehicle. Read the content limitations.