[Frenchyakamd]

I've got a '00 zetec atx. So, the other day I started to hear a knocking/tapping sound when I accelerate. It's hard to pinpoint the sound, but it's a steady sound from the engine bay. I can also feel the knocking very well through the gas pedal. Now, It only happens when I accelerate; the second I lift off the gas pedal, the sound stops. Even if I'm cruising at freeway speeds but I'm not accelerating, no noise. Any idears?