Hi everyone. So i have a 2006 350z with about 83k on it and since i bought it a couple months ago, there has been a weird whining noise. It almost sounds like a sequential transmission. I had a friend rev it when its stationary and it sounds like it comes from the back of the engine bay. Its really annoying. When the car is cold and idling, the sound is present but when it warms up, the sound goes away until you start driving. On normal roads going 40-50 mph, you can hear it. From 70-85 mph, the sound is at its loudest and its really annoying. Im no expert so thats why I need help. Just to mention, the sound gets louder with the rpm. Whenever i let my foot off the gas on the highway, the sound goes away. I will be doing an oil change soon to see if that might help, otherwise, please help. My hears hurt