VANOS death rattle?

[01SG]

My car has developed a racket that I pinpointed to the front of the valve cover by listening with a screwdriver. It started as a droning noise a few weeks ago and has developed into a more pronounced rattle at 2-3,000 rpm. It seems to have got worse and I will no longer drive it after replacing the chain tensioner failed to fix it. It goes away when the car warms up except for a less audible rattle sometimes when the revs are dropping past that same point, so I don't think it's a rod. It does not happen at idle.

Time to do the VANOS? More importantly: am I correct to assume it's not a spun bearing if the noise goes away when oil is up to temp/at idle?

[01SG]

Added a video

https://youtube.com/shorts/dU6UWpm3PlU?si=wfy3yLXQAXckYafH

[Slideways]

It sounds like the intake cam bolts are loose. If you can remove the valve cover, you can look at back of bolts to see if they are backing out. Best to stop driving it until you or a specialist can take the valve cover off and check things over.

[sapote]

The rattling noise is continuous, so I don't think it's typical vanos piston shaft roller bearing plays noise. I'd check valve clearance, and cam follewers to cam lobe surface condition.

[01SG]

The rattling noise is continuous, so I don't think it's typical vanos piston shaft roller bearing plays noise. I'd check valve clearance, and cam follewers to cam lobe surface condition.

Hmm, the valve clearance was never far off on any of the three or four adjustments I've done over the years, and the cams looked fine last time I had the cover off-but that was 15k miles. Would a noise from that appear more gradually? Because this was rather sudden.

I'll be taking a look soon in any event. The cam bolts were my first thought as well.