V8 engine 'clacking' sound when accelerator released

[tbenesch]

Curious if anyone has come across this before. I have a 2012 5.0 V8 e70. There is an annoying 'clacking' sound (like something is loose) from the engine bay that occurs when I release the accelerator at speeds from 10mph+. As soon as I lift off the accelerator, the clacking noise occurs until about 5mph and then goes away. It also goes away if I just tap on the accelerator, and then comes back as soon as I let off the accelerator. It doesn't sound when I'm in Park or Neutral and am sitting still. Any thoughts?

[andrewwynn]

Take an audio recording and share it.

See if the sound goes away when coasting in neutral. Eg reproduce the sound starting to coast then put the car in neutral say at 10-15 mph and back into drive see if the sound returns.

The goal is trying to establish is the sound from the engine or drivetrain.

[tbenesch]

Hello Andrew,
Great suggestion. It does go away when I shift into neutral and comes back when put back into gear. So, it sounds like it is a drivetrain related issue. I tried to record the sound, but got too much wind noise, so I'll try it again in a parking garage enclosure which makes the clacking noise more prevalent.

Troy