F82 Noisy exhaust camshaft

[Notsofastfrank]

I recently had my brake fluid changed at BM Connected in Braintree, excellent service and I will definitely use them again. Matt the owner mentioned that the exhaust camshaft was one of the noisiest he had heard and should get it looked at as still under AUC warranty.
I called the local BMW dealer, Sycamore Peterborough, who told me to ring BMW assist as they would be able to get the car booked in faster than their first available date of 3 weeks time. Called BMW Assist who had a tech with me in 90 minutes. He agreed it was noisy and arranged for Sycamore to look at it tomorrow. A loan (hire)car will be dropped off at Sycamore, an M340i with a £2k excess!! I’ve taken out hire-car excess cover as it was only £25. Impressed with the service so far. I’ll try and upload the sound tomorrow before I take it in. I always thought the engine was noisy, especially on cold start-up but have not had another to compare it to.

[benm3evo]

Can you actually hear an exhaust cam specifically?? I know the injectors are loud on these & make a ticking noise (even worse with the engine cover off) but I didn't know it's possible to hear a camshaft

[Notsofastfrank]

It was a whirring noise and was not constant, tending to rise and fall. Definitely noticeable once it had been pointed out.
BMW we’re pretty good, first sending out someone from BMW Assist and then arranging for the local dealer to look at it and arranging a hire car.
They agreed it needed looking at and after investigation realigned the camshaft. No idea of cost as it was under warranty, they did mention it was 9 hours labour, so would probably be around the £2k mark as no major parts involved. It is definitely quieter on cold start-up now.

[zedx19]

How does the exhaust camshaft come out of alignment??

[Notsofastfrank]

I believe (but stand to be corrected) that there is a basket which holds one end in place which can come loose, possibly through not being torqued correctly at the factory.