Greetings everyone. I recently purchased a 2001 Navigator with the 32V 5.4 and Im trying to resolve some issues with it. I have looked through the threads searching for information and I do have a good idea as to why its running bad but would like have some second opinions. Here are the issues:

1. Cranks and starts fine on cold start up. I can give some throttle and the rpms return to normal with no hesitation. After it warms up it still idles fine but once you give it some gas it falls on its face and wants to die or does die. From what ive read it could be a bad fuel filter, egr system, or vacuum issue.

2. After running for 5 to 10 minutes it has a hard time cranking over after being shut off. The battery is new and test fine and once it sits for 10 to 15 it will crank over like it should. Ive read that it could be the starter relay or the starter itself, or the connections are corroded.

The CEL is not on and doesnt come on when it acts up, I have tried to pull codes but nothing is stored on the computer. I have replaced the idle control valve for starters and have a new erg valve ready to go on. I had a taurus do this and it ended up being the pcv elbow sucking air but I don't see any rot, cracks, or bad spots on the Navigators pcv system. I appreciate any insight, thanks!