Get a high pitch whining when I hit WOT. Any ideas. I have a stock intake with the GOTTS mod and an AFE Insert cartridge. Can't seem to find anything out of place.

 

Could be your alternator bearings telling you it's time to replace them.

 

What about idler or tensioner pulleys

 

Could be those as well, but the alternator bearings has a long history of causing this exact symptom.

 

Is it better for me to maybe just replace the whole alternator if that is it since it's oem from 2006. And how would I actually diagnose the alternator without driving it.

 

Check for play in the shaft of the alternator, and see if it feels smooth when spinning it freehand.

It's easier to replace the alternator than replacing the bearings, but I'd advise against a parts store rebuild.

 

Ok thanks I will check that out.