engine noise when accelerating like fan or tappet noise. 3.5 se

If the tapping or clicking increases as you accelerate and becomes faster. This could be what is known as a 'tappet,' or the upper valve train. The causes could be a number of issues starting with a worn part. It could also indicate that the oil pressure is low. Check your oil pressure gauge when you hear this sound and follow guidelines to determine the exact problem. Take the dip stick out and make sure you have enough oil in there.