98 F150 4.2L V6 Automatic sqealing noise after starting when cold then after short warm up goes to chirping sound. I thought it was serpentine belt or pulley but sound still happens after I removed the belt and started. It is driving me crazy trying to find. Could it be noise from some sort of emissions device, valve, sensor, etc.

 

[ul][*]There are 3 ford technical service bulletin's on this engine for vacuum leak's or intake manifold leak's.[*] Another tsb is for a accessiory belt noise when cold.[*] Another for cold start engine noise.
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