It is a rattle coming from the front pass side of the engine bay. It happens mostly when I step on the throttle while the trans is engaged. If I throw it to neutral and step on the gas, the rattle does not occur. It also rattles when the car on and parked with a/c on. I haven't put my car on jacks yet to look under but I looked inside the top of the engine bay to see if I could find anything. No dice. Any ideas?