1998 e38 m52tu loud rattle/tick

[e36headcase]

So my e38 is talking to me, it make a rattle noise but not untill its warmed up at idle, driving you cant hear it but its there only when the engine is warmed up.
Its a rattly noise thats coming from the front right of engine where the power steering and oil filter housing are, it sounds like its coming from under the manifold?!?
It sounds like something is loose but ive checked all the obvious things and its nothing obvious.
Im hoping its not the vanos.
Im going to change the oil and see if that helps.
Any ideas?!?

[MauiM3Mania]

Moved to the model specific sub-forum.

[Mayorchuck]

Have you ruled out the purge valve? It sits by itself near the oil filter and recirculates fuel vapor from the tank back into the engine. Mine seems to be louder during the winter months. The only other thing that comes to mind is a loose spark plug. Both these are more of a tick than a rattle however.

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Can you make a video of the noise?

[e36headcase]

I tried disconnecting the disa, no change, and the fuel breather/circulator, no change.
I will check spark plugs when i change oil, the car is currently off the road.
I will have a video for tomorrow, when im back from work.

[e36headcase]

https://youtu.be/3Gi6nEu__-U

Heres a video, so i decided to let the car reach temperature and then the noise came, so i turned it off removed the fan and both belts, noise gone! So its a drive belt problem, ive only got one idler so i will start with that. Any other common problems?!

[Timm]

No, it's definitely the belt - all the other bits make much faster noises.....

[e36headcase]

Theres slight play in the alternator shaft, ive got a spare that i know is working fine, i will try that, and ive got a spare tensioner too along with pulley. The pulley sounds like a roller skate wheel, should it?!

[kouks]

Theres slight play in the alternator shaft, ive got a spare that i know is working fine, i will try that, and ive got a spare tensioner too along with pulley. The pulley sounds like a roller skate wheel, should it?!

No, it should be smooth and quiet and should not have any resistance.