ok every once in a while my diesel superduty surges real bad. it just wont build boost. it jus keeps dumping the turbo pressure out of the waste gate. does anyone know how to fix this or what is wrong?

 

If it is a 6.0L, the variable vane turbo used on them does not have a waste gate. That is why you get the "snuffling" sound (a.k.a. "turbo fart") when under heavy throttle & quickly letting off. There is no place for this unneeded boost to escape, so it reverses flow & exits the way it came in.

That being said, one of the more common ailments for the VVT is stuck vanes. Do a bit of searching here in the Super Duty and over in the 6.0L forum. There are more than a couple threads regarding this issue. A few of those threads have input on how to diagnose & remedy.