I'm t/s my car having a fuel smell after the engine warms up and someone suggested the evap system. I tested the solenoid and the fuel pressure control valve and both seem to be working. When putting 12vdc to the solenoid it opens as should, the contol valve opens when putting some vacuum to it and closes without vacuum like it should. So I'm asking, do these canisters ever really go bad, and how can you tell?