I just noticed today that I have a chirping/squeaking sound when I turn the car off, just as the engine is dying down. It almost sounds like a bird or a cricket. Anybody know what this is or if I need to worry about it? I'm under warranty so if its a problem I wanna get it fixed. Help me please...I have a 99 4d ls manual w/ 35k. The only mechanical change I've made is a short shifter.