idle problem

From what you have described it sounds like you have a serious Vacuum leak. Rcheck all your vacuum lines for leaks and be sure all Unused vacuum ports on the Intake Manifold are capped. The 5.9L 360 is notorious for intake manifold and Intake plenum gasket leaks. You can try to isolate the leak y starting the engine and using a can of starting fluid or Carb cleaner, spraying around the intake manifold where it meets the cylinder head and note any change in RPM. If so then you have found your leak, I caution you on this method however, the liquids I mentioned are Extremely flammable and Will cause a fire if coming in contact with a spark or very hot surface such as the Exhaust manifold. Be Very careful. B est bet is to go ahead and replace the intake manifold and Plenum gaskets. After removing the Intake flip it over and you will see the plenum bolts to remove and access the gasket.

I figured it out, it is the plenum gasket. I used an endoscopy with my phone to look inside the intake. Instead of just replacing the gasket for it to happen again if the thin factory plate is warped, I opted for an aftermarket intake made by Hughes engines and edelbrock that eliminates the plenum. It can be found here http://www.hughesengines.com/Index/products.ph p?browse=search&search=Air+gap&submit=Go They also offer a 1/4" think aluminum plenum that won't warp and blow the gasket, found here http://www.hughesengines.com/Index/products.ph p?browse=search&search=Plenum&partid=30712

Hey, that's a great idea using an endoscopy with your phone to look inside the intake. You made the right choice by investing in an after market intake to eliminate this problem from reoccurring. Thanks for the links to the Hughes products. They are about the best out there in my opinion.