whining noise in engine compartment

2007 6 cylinder.

In low rpms there is a whining noise and the truck seems sluggish. I changed the waterpump, serpentine belt and had the transmission flushed with BG additive. Any suggestions. I have 236K miles.

Thanks

 

Did you check your idler’s when you replaced your belt? Common problem, not sure if it will make your truck sluggish but it will make a whining noise or rattle. Alternator?

 

After all the idlers (3) and tensioner (and alternator) there is the PS pump and AC compressor to check.
Then front wheel bearings, driveshaft/coupler freezing/failing, and then throttle body/MAF dirty for power.
Vacuum lines rotting out also. Good hunting.

 

I've heard many noises from vehicles (not necessarily Tacoma)
such as clicking
which is usually a worn CV joint

last time I heard what would be described as whine,
was a failing power steering pump