Please help! 4.6 Squealing not serpentine related.

[CallMeSyd]

Just picked up a 2004 Explorer NBX today with a 4.6. Bought it from a girl who says she changed all the coil packs and when she went to crank it, it now has a squealing sound coming from the driver side valve cover area. Someone checked the codes but cleared them and it has not been run enough to generate anything new. She claims that the vehicle is in limp mode, which I am not quite sure how to confirm. I have not had time to check anything or begin trying to diagnose the problems. So far just the squealing (sounds like a bad pulley bearing but belt, pulleys, etc. are fine) and it idles a little rough. Burning oil smell from exhaust but maybe just cause it's been sitting for a while? Is there a cam synchronizer in the area where the squealing is coming from perhaps? I will try and look at it in the morning and see if I can figure anything out, but any input could be helpful!

 

[94Eddie]

The 2V 4.6L doesn't have any VVT. Maybe pulling and inspecting the spark plugs will tell you something.

 

[TechGuru]

Start it up without the belt installed for a few seconds.

Only thing I can think of that would sound similar is a whistling vacuum leak.