2003 Z06 with cam and CNCd 243 heads. Recently Ive developed a high pitch wine between 2500 and 3000 RPM when accelerating in any gear. The odd thing is that when stationary, with the clutch depressed, in any gear, and revving the engine, there is zero wine in the same RPM range. You would think that if it were an exhaust leak or vacuum leak, it would be present whether the car was actually accelerating or just the engine being revved.

Im a bit stumped as all indications point to something other than the engine but at the same time, it only occurs under acceleration between 2500 and 3000 RPM. Any help would be much appreciated.

 

Belts (motor, AC)
Belt tensioner
Idler pulley bearing.

Good place to start and cheap parts to replace.

Chad

 

I agree it is something that is under load when you are driving.Thats why it does not do it when you are stationary reving. Check your belt tensioner especially it can be slipping and there is an easy fix for that. Just by a
Corvette Engine Belt Tensioner, Billet, LS1/LS2/LS3/LS6/LS7, 1997-2013 Part # 55477 Eckler's