gforce

I have a symptom on my 02 Dodge auto with 154k miles after about 20-30 minutes of running or more when I come to idle and go to park, turn off a/c and let the turbo cool within about 20-30 seconds the engine begins to cutout completely as if you are rapidly turning the switch on and off. If I leave the a/c on or stay in drive it will not happen so its when the engine has no load at all. I recently changed my vp44 for fault codes but this problem was there before and still remains. I have 275 bosch injectors, 20 psi fuel pressure, EDGE E-Z , custom turbo, 4" exhaust and KN air filter. I've run this on a snap-on scan tool and on Cummins Insite and the data all looks normal, thinking about using a lab scope on the cam sensor and maybe some of the other sensors. The only other symptom I have is when the rpm is coming down coasting to a stop at around 1000-1100 rpm, it doesn't cutout but just runs real lopey. Any experience with this or ideas would be greatly appreciated.