Supercharger issue

My 1996 park ave, seems to build boost off the line as it pleases. Some times you accelerate and it will ease off then next thing you know your speeding. How is the boost controlled on these cars?

The boost is controlled by the boost valve, location as shown in pic below. Have you checked the vacuum lines and the fitting on the boost valve housing. With age, the plastic vacuum fitting becomes brittle and the port connection will crack if anyone touches it. You could have other problems, but check these items first.

http://img24.imageshack.us/img24/4874/plugwires1.jpg