Is this a normal diesel idle? Or bottom end knock - VIDEO

[SMOKEY53]

Hi guys

I'll preface this by saying I'm new to diesel ownership and I've put only 100km on my car in the 3 days I've owned it. I know diesels can clackety clack and carry on, so I'm not sure if this noise is normal or not - but it doesn't feel right.

I guess normally I'm in the car with the doors shut so I haven't really noticed this noise before, but I'm somewhat alarmed. This sounds to me like a bottom end knock. The car has 115km on it and what I assumed to be reasonably sound dealer service history.

I've taken a video so hopefully someone can help.

Diagnosis so far: Have run BMW Scan 1.4.0 - no error codes. Car is at operating temperature. Oil levels ok. Sounds quiet at start up but then at about the 20 second mark the knock starts to amplify. Noise is louder under the car and with the oil cap off, I can't really link the noise to tappets.



Any help would be hugely appreciated. It's a public holiday here tomorrow and I'll be stressing until I can get it in to my mechanic!