Error code P0440 on a 2003 CTS, most probable cause?

Question

P0440 fault code first came in in early December. After replacing the fuel cap the code did reappeared in about 2-3 days later. A visual inspection found a melted hose on the right side of the engine. The code was cleared however, in 3 days it was back again. I should note that the car is running just fine. There is no issues with its performance. What would be the most probable cause for this fault code to keep reappearing?
Louis

Answer 1

For P0440 to set and there is no other code present, the most common is the FTP (fuel tank pressure) sensor , The EVAP system monitor the FTP sensor, if the condition is not correct you set a P0440