2007 chrysler aspen 5.7. starts runs up to 2000 rpms drops to 0 and dies.

Ahhh, stop changing parts! How much money have you spent for parts when a simple diagnostic test and consulting a qualified technician would lead you down the proper path, much likely for less money spent! For me, this sounds like a possible vacuum leak at the engine, or perhaps an un-metered air leak. It could also be the result of an idle control valve sticking. Good luck.