I have a 2g N/T. Recently I've been experiencing a loud knock when accelarating. This has happened to me before. I had the engine replaced under warranty and it is doing it again. Last time the mechanic told me that the coil pack caused the knock and the engine failure. He replaced the engine and coil pack and it still hasen't helped. It makes a slight knock at idle but really sounds bad at speed. It even downs out the sound of the cold air intake. Does anyone know what this is, and what can be done. The guy is unwilling to replace the engine even though its still under warranty. PLEASE HELP!