I was asked to see if I can help you out here.
This system is designed to maintain a pressure of 30-50Mbar of pressure. Anything over that is released through a vent valve to the charcoal canister. I would suspect that your has either a restricted line or a defective vent valve.
Here is a diagram of the system. #51 is the vent valve.
Friday, September 6th, 2013 AT 3:24 PM