I guess I am glad that I am not the only one with this issue. I have 90,000 miles on my 2001 Malibu and it just started making the noise a few days ago. Along with the noise came a lose of horse power (even when not whistling). Also the tranmission seems to be shifting up and down more often than before. I also sensed some hitching in either the engine or the transmission.
The person that says it sounds like crickets is right on. That is just what it sounds like.
Mine starts at 2700 RPMs and gets much louder through the next 200 RPMs and only slightly increases beyond at. Yesterday morning I was climbing a steep grade and the car dropped into low gear and revved up to about 4500 RPMs. at 4500 RPMs it made a noise like a tennis call got stuck in the nozzle of a vacumn cleaner (like a Fwoomp noise) and the whistle went away. At that moments the horsepower returned and the hitching stopped. It remained that way for the next 10 miles. The next time I started it up, I took it to my garage and they drove it, tested stuff and can't find it. They tell me it will have to get worse before they can find it. I can't imagine it can get worse without catastrophic failure of something. It is very loud. Very loud. Easily heard over the radio and definately sounds like a vacumn.
The person that says it sounds like crickets is right on. That is just what it sounds like.
Mine starts at 2700 RPMs and gets much louder through the next 200 RPMs and only slightly increases beyond at. Yesterday morning I was climbing a steep grade and the car dropped into low gear and revved up to about 4500 RPMs. at 4500 RPMs it made a noise like a tennis call got stuck in the nozzle of a vacumn cleaner (like a Fwoomp noise) and the whistle went away. At that moments the horsepower returned and the hitching stopped. It remained that way for the next 10 miles. The next time I started it up, I took it to my garage and they drove it, tested stuff and can't find it. They tell me it will have to get worse before they can find it. I can't imagine it can get worse without catastrophic failure of something. It is very loud. Very loud. Easily heard over the radio and definately sounds like a vacumn.