O.K. This may sound very elementry but I have whistle sound under hard acceleration from 3200rpm to about 4300rpm. I have tried to spray carb cleaner around the intake tract up to and including the intake manifold and throttle shaft. Now with that being said it will only make the sound under a load,....stand with the hood up and it will not make a sound.

Thanks for any help,.....scratching my head on this one!!!

 

what intake do you have?

 

Stock,...nothing has changed under the hood! That is why I can't figure the odd noise.

 

can you trace where the sound is coming from?

 

No,....it will only do it under a load. If I could safley strap myself to the engine, it would be easy. I have even gone as far to put it on a lift and run it through the gears. I have run it up against a wall trying to figure witch side it was coming from and honestly ,.....it didn't help!! I couldn't here a difference from one side to the other. I thought it could be an upper butterfly problem.

 

Could just be the intake. They do whistle, it's the sound of air getting sucked in. Normally on stock intakes it's not sucking enough to hear it. Maybe you just have a good flow.