Gas Cap Code

I got the P0440 code. 1999 Olds Van. Every once in a while when I removed the gas cap I would hear pressure being released from the tank. I replaced the cylinoid by the EVAP canister. I also dropped the tank and replaced the Pressure Sensor on top of the tank. I also put a new gas cap on the vehicle. No luck. My light is still on. Same Code....Any thoughts.

I'd check for perforated or cut hoses. Basically you're looking for anything that would cause a leak in the EVAP system.....looks like you've replaced the more obvious things. Next time I'm home, I'll look at the service manual and see if there are other things listed to check....

Glen

Glen, Thanks for the reply. Still no luck. I could not find any problems so far. Still searching?