Well I tried a search on this with no luck so I need some help. First off let me say that I am a certified technician (GM) so I know what I am doing, just need a little help. I have a 2001 ZX3 and for the longest time I have had a severe whine coming from what sounds like one of the accesories. I.E water pump, timing belt. alt etc etc. Well, I came to the conclusion that the timing belt idler was making noise. So I replaced the belt, idler and tensioner. Well, didn't fix it. I know it's an engine noise as it increases with RPM not MPH. I have a new alternator and swapped serpentine tensioners with no luck. Anyone had any similar experiences? Please help this is really starting to annoy me. Thanks in advance!