Drop the oil pan and see if you have bits of chain guides in the pan. If you find chain guide bits in the oil plan, go to plan B.

If it's a 4.4, sure...I guess. Not on a 3.0.

:iagree: Good catch.

Yeah Ive had few issues to deal with so have left it. But need to re address now asap. Still unsure or the rattle. Thought it may have been the cats on exhaust. Put a camera up there and seemed ok. Still need help if anyone has any other ideas to try or anything. Thanks guys.

If I can get some time, I am going to pull the front end of my motor off and replace as I reassemble. Timing, vanos, gasketry..everything...so I can look at putting some turbos I have on it.

I have essentially that same noise.

I would see if I could pinpoint the source of the sound with an auto stethoscope. I wouldn't start tearing it down without knowing the core problem. The reason being that there are several potential causes and you may go through all the work and replace all the associated parts and still have the issue when you are done.

This does not sound like chain. This sounds like stuck lifter. And it gets quiet when oil makes it through. What oil are you running in there, and when is the last time you changed it? Please do not say you change it every 10k miles.

The crux of it all lads.

Started out attempting to fix this myself. Did timing chain tensioner. No difference, thought it did but didn't. So then pulled off rocker covers and stuff did a brief check over all good. Next step was to take to highly regarded bow repairer - however not bmw themselves. These guys ring me. Saying its a shroud we found it its all good. They removed the rear part of exhaust heat shroud which for one clearly bloody needs a heat shroud so leave it on, and then when I go to pick it up, they say ah na it's not the heat shroud it's the exhaust cats have fallen apart. Even though they removed the heat shroud!!!!
Took apart myself and threw a camera up the exhaust from underside to inspect internal cats. Looked sweet as. Nothing a miss and all in tack.
So the other point u have just put to me about oil. Not a lifter. Noise is intermittent. Realistically the noise only occurs when u take load off motor. So as you take foot off excelerator something is rattling or vibrating. And you can only hear it when ya driving next to a wall or something like that for the sound to bounce off. And yeah it's only on release of excelerator. Oil changed every 10 thou or more and today put thicker oil in it as we have extreme heat here in Perth and the oils too thin for our conditions so went 5w by 40. I was running 5w by 30.
So back to lifter comment. I'm open to ideas and questions but don't think it is lifter as sounds like an external noise hence the cats and the heat shroud.
Also, sometimes u start it and it doesn't make the noise for a couple of mins, sometimes it does. Sometimes u can put the aircon on and that can quieten it down for a short period, but never always. Only sometimes.
So for a plumber I have racked my brain and even guys like yaselves brains to get head around it. Actually took it to genuine bmw dealer yesterday, tentatively to see what they thought and they won't look at it till I book in for inspection for 220 bucks.
Over it.
Think I might look into this stethoscope thing otherwise after that I'm rippin it to bits. So sick of it and the cost already over 1500 from supposedly great bmw specialist mechanics with no direction or being any closer to rectifying.
Where would u ft a stethoscope from could u hire them? And are there actual automotive ones as well?

Thanks again guys.

Will post a new video shortly so you guys can here it

The original video does sound like a cat rattle like interior of the cat could be coming apart.Do you notice any unusual smells from the exhaust? If it is a chain rattle then it will be there all the time at all idle levels. Its not vanos. Normally the vanos start out quiet on start up up become more tractor diesel like when they warm up. Double check he cats out.