Ok, I thought I fixed my idle problem with a apps. It ran just fine for about 4 days no rump rump or anything, well its back. List of things done - second new apps,vp44,cam sensor,fuel pressure airdog 13.50lbs,tried ecm off another truck,tired turbo off anothre truck. One thing I have noticed is it only does it when eng. has been driven at hwy speed for a little while,does not rump rump at all when just idel around town. :thud

Wow tuff one here. Can it be possible that it is sucking air somewhere?

Well I dont know. Apps seemed to fix it and a few days later it starts all over again. :confused:

Well that gives a clue... You might check over your APPS wiring and make sure there is no problems... :confused: