03 Hemi developed a whistle which is throttle related. Happens more when cold. Whistle go away and comes back by changing throttle position. Cant simulate it in neutral with truck stationary. Checked some vacuum hoses and torqued throttle body bolts. Anyone have experience with this. My next thought is to check fuel canister and purge valve. No codes yet

 

I have an 06 with a hemi and had a whistle under load that was caused by an exhaust manifold leak. Broken bolts caused the gasket to flutter and make a turbo-like whistle sound.

 

Thanks Tony. Its definitely throttle body related. I can change the pitch of the whistle by feathering gas pedal and making a small angle change to the TB air valve. May end up taking TB right off for examination.

 

Is there any carbon build up?