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DTC P0497: Evaporative Emission (EVAP) System No Flow During Purge
Circuit/System Description
The control module tests the evaporative emission (EVAP) system for a large leak, or a stuck closed EVAP canister purge valve. The control module monitors the fuel tank pressure (FTP) sensor signal to determine the EVAP system vacuum level. When the conditions for running are met, the control module commands the EVAP canister purge valve OPEN and the EVAP vent valve CLOSED. This allows engine vacuum to enter the EVAP system. At a calibrated time, or vacuum level, the control module commands the EVAP canister purge valve closed, sealing the system, and monitors the FTP sensor input in order to determine the EVAP system vacuum level. If the system is unable to achieve the calibrated vacuum level, or the vacuum level increases too slowly, a DTC sets.

Diagnostic Aids
• A loose, missing, or damaged fuel fill cap can cause this DTC to set.
• A stuck closed, blocked, or restricted EVAP canister purge solenoid valve, can cause this DTC to set.
• A blockage or restriction in the EVAP canister purge solenoid valve vacuum supply hose, EVAP canister purge solenoid valve purge pipe, EVAP canister, or vapor pipe, can cause this DTC to set.
• A temporary blockage in the EVAP canister purge solenoid valve, purge pipe or EVAP canister could cause an intermittent condition. Inspect and repair any restriction in the EVAP system.
• To help locate intermittent leaks, use the J 41413-200 Evaporative Emissions System Tester (EEST) to introduce smoke into the EVAP system. Move all EVAP components while observing smoke with the J 41413-SPT High Intensity White Light. Introducing smoke in 15 second intervals will allow less pressure into the EVAP system. When the system is less pressurized, the smoke will sometimes escape in a more condensed manner.
• To improve the visibility of the smoke exiting the EVAP system, observe the suspected leak area from different angles with the J 41413-SPT .
• Observe the Freeze Frame/Failure Records vehicle mileage since the diagnostic test last failed may help determine how often the condition occurs that caused the DTC to set. This may assist in diagnosing the condition.

The check engine light went off on it's own ? Before replacing the purge solenoid did you test the evap system by smoke checking ? Would have other code's besides P0455 if purge solenoid was bad. DTC P0455: Evaporative Emission (EVAP) System Large Leak Detected
• Inspect for a loose, missing, damaged, or incorrect fuel fill cap.
• Inspect for a damaged fuel filler neck seal surface.
• A blockage or restriction in the EVAP purge solenoid valve, purge pipe, EVAP canister, or vapor pipe, can cause this DTC to set.
• The EVAP system can be filled with smoke more quickly and completely by opening the system opposite the end where the smoke is injected. For example, when injecting smoke at the service port remove the fuel fill cap, or temporarily leave the vent open, until smoke is observed, then close the system and continue testing. If using a fuel cap adapter at the filler neck, use the J 41413-VLV at the service port to allow the system to fill faster.
• To help locate intermittent leaks using the J 41413-200 , move all EVAP components while observing smoke with the J 41413-SPT .
• Individual components can be isolated and tested using adapters in the J 41413-300 .
• A condition may exist where a leak in the EVAP system only exists under a vacuum condition. This type of leak may be detected by using the scan tool Purge/Seal function to create a vacuum in the EVAP system and then observe the FTP parameter for vacuum decay.

Well if you can not locate this with your Ear.... and find the correct position of it. All is going to have to be done in an inside air free environment and do a smoke test by blowing cigar smoke it threw that specific line looking for smoke coming out of the line in question while also moving it in every direction while smoke goes threw it. This is truly for a person that loves a good Cigar of course HA HA. But a garage will do it fairly cheaply as well,or you can do with a cigar producing a lot of smoke in the same general area just moving it around what you think is the suspect vacuum line. The engine compartment will be much harder as the engine fan will disperse the smoke rather quickly. Remember to rate my solution and give testimonial this is how i earn my achievements here in FixYa Thanks in advance.

Have you checked your timing belt or chain?