i did a little bit of reading concerning a hissing sound that may be from my intake... now i've just read something about a "yo-yo" on MCSa, is this the same problem that i'm bringing up? if so, can the dealer fix as i am under my warranty still?

and can someone also explain what exactly is a "yo-yo" and how it sounds like?

 

When does this problem occur for you?

 

well i dont know if it makes a noise or anthing but, the "yo-yo" usually implies to the bypass valve. it will kinda open and close while your ar partial-full throttle and make your car have a sorta accel--decel--accel--decel feel .

 

when the car is about to shift gears around 2500-3000 rpm i can hear like a whistle from the left side engine.

 

Does it make this same whistle noise when you shut the engine off for a second or two?