1966 Crown Coupe, 2016 200 S AWD, 1962 Lark Daytona V8.
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P0455 is a large evaporative leak somewhere between the gas cap and the purge solenoid. 'Large' meaning probably greater than .020". http://www.obd-codes.com/p0455
Make sure that you have a non-venting gas cap. Use the underhood vacuum diagram label to trace the components, lines and hoses. You shouldn't be able to blow through the purge solenoid with it off. Make sure that the rubber hose connector block to the purge solenoid is secure and fits firmly to the plastic fittings.
You are going about the diagnosis the correct way with a visual inspection for the more obvious cracks, holes or rustouts. Many rubber hoses and components dry-rot and crack at the ends where they push onto a metal line.
It was around this era when Chrysler went from an active LDP (leak detection pump) system to a simpler, passive NVLD (natural vacuum leak detection) system. If the leak detector switch doesn't close with the system under slight vacuum within an allotted amount of time, it means that the system is breached-to-air and an evap leak fault code is triggered.
At the shop we have a smoke machine that will blow a cool, UV-dye containing vegetable oil-type smoke into a sealed evap system under low pressure. You will find the leak at the point where the smoke is exiting. This makes finding these more difficult evap leaks much easier.
Make sure that you have a non-venting gas cap. Use the underhood vacuum diagram label to trace the components, lines and hoses. You shouldn't be able to blow through the purge solenoid with it off. Make sure that the rubber hose connector block to the purge solenoid is secure and fits firmly to the plastic fittings.
You are going about the diagnosis the correct way with a visual inspection for the more obvious cracks, holes or rustouts. Many rubber hoses and components dry-rot and crack at the ends where they push onto a metal line.
It was around this era when Chrysler went from an active LDP (leak detection pump) system to a simpler, passive NVLD (natural vacuum leak detection) system. If the leak detector switch doesn't close with the system under slight vacuum within an allotted amount of time, it means that the system is breached-to-air and an evap leak fault code is triggered.
At the shop we have a smoke machine that will blow a cool, UV-dye containing vegetable oil-type smoke into a sealed evap system under low pressure. You will find the leak at the point where the smoke is exiting. This makes finding these more difficult evap leaks much easier.