Use simple seal, command, and symptom-correlation checks to prove whether the purge valve is actually leaking before you replace it.
If the engine restarts poorly, idles rough, smells rich, or blows brief black smoke mainly after refueling or hot soak, that timing is real evidence. A purge valve that leaks when commanded closed can feed stored vapor into the intake exactly when the engine is most vulnerable to flooding. That pattern is very different from a rich condition that is present cold, hot, loaded, and cruising all day long.
The most important purge-valve test is not whether it clicks. It is whether it actually seals. Remove the valve if access is reasonable, leave it unpowered, and apply light vacuum to the manifold side. A healthy normally closed purge valve should hold. If vacuum bleeds off, the valve is leaking internally and can absolutely cause P0496, post-refuel rough idle, or rich restart behavior.
After proving the valve can seal, verify that it opens and closes cleanly when commanded. Bench power or scan-tool control can help here, depending on the platform. The point is to confirm both directions of behavior: closed means sealed, open means flow. A valve that only clicks loudly but still leaks or sticks is not passing the test just because it makes noise.
If the complaint happens mainly after getting gas, temporarily isolating the purge line during diagnosis can be a strong tie-breaker. If the engine suddenly stops loading up on restart, idles smoother, and no longer smells as rich, you have evidence that vapor ingress through the purge path is central to the complaint. That is stronger than replacing the valve because the internet said P0441 always means purge.
A purge valve can test good and still be fed a bad story by the rest of the EVAP system. A fuel-soaked canister, repeated topping off, restricted vent path, or irrational tank-pressure reading can overload purge flow and make the engine act rich after refueling. That is why P0441 and P0496 often deserve canister, vent, and pressure-context checks instead of one-part tunnel vision.
Negative fuel trims that spike after refueling, then improve as the vapor clears, fit EVAP flooding much better than a leaking injector that stays rich all the time. If the rich condition is constant on every warm idle, cold start, and cruise event, widen the diagnosis. If it clusters around refueling, hot restart, and vapor-heavy situations, the purge path earns the front seat.
Replace the purge valve when it fails a sealing or command test. Keep digging when it passes but the complaint timing still screams EVAP, because the canister, vent hardware, hose routing, or pressure-sensor story may be the reason the engine is being fed vapor at the wrong time. The goal is not to name the most famous EVAP part. The goal is to prove where the unwanted vapor is entering and why.