What is P0455
Experiencing poor gas mileage along with the P0455 code unfortunately you might have an issue with the EVAP system so the P0455 code stands for evaporative emission system leak
Detection of the Code
Detected this code will be set when you have a large leak in the EVAP system in some situations we could have a vapor blockage in the EVAP system which the ECM could interpret as a leak
The Purpose of EVAP system
EVAP system is to store fuel Vapors created in the fuel tank and transfer them into the combustion chamber through the intake manifold where they get burned off in the process
The potential components in the EVAP system that can trigger the P0455 code one common cause is a :
1 faulty fuel
if the fuel cap is damaged or has a torn gasket it won’t create a proper seal this creates a gap for the fuel Vapors to escape leading to a leak in the system also always make sure you hear at least three clicks when closing the cap if you don’t close it properly this can trigger the P0455 code the
2 Fuel tank filler
A faulty fuel tank filler if it’s corroded damaged or cracked fuel Vapors can escape and cause a leak in the system
3 Stuck open purge valve
Stuck open purge valve cause for the P0455 code is a stuck open purge valve the purge valve opens when it’s commanded by the ECM to transfer fuel Vapors from the charcoal canister into the engine for combustion under normal operating conditions the purge valve remains closed and only opens during the purging process as directed by the ECM if the purge valve gets stuck open when it should be closed it creates a constant vacuum in the EVAP system this leads to the P0455 code in some situations I’ve seen a stuck closed purge valve that can cause this code
4 Bad charcoal canister
A bad charcoal canister if it’s damaged or has any large cracks in it fuel Vapors can escape creating a leak in the EVAP system the next possible cause for the
5 Fuel tank pressure sensor
P0455 code is a malfunctioning fuel tank pressure sensor the purpose of the sensor is to monitor the pressure in the fuel tank and send this information to the ECM if the fuel tank pressure sensor’s faulty it can send false readings of the pressure to the ECM making it believe that there’s a leak in the system the car’s computer will then turn on the engine light
6 Evaporation hoses:
Evaporation hoses if any hoses have cracks or get damaged they can cause a large leak also sometimes one of these hoses can become loose which will cause a leak
7 Evaporation canister vent valve:
Evaporation canister vent valve this component is supposed to be opened during normal operation and closed when the ECM test for leaks if the canister vent valve remains open during testing the ECM will interpret this as a large leak and Trigger the P0455 code
8 Damaged fuel tank:
component that can cause this code is a damaged fuel tank this isn’t very common but it’s still possible now one of the best ways to find the leak in the EVAP system is to use a smoke machine
9 Bad ECM:
trigger this code is a bad engine control module however this should always be your last option I recommend testing all other parts first before blaming the ECM
