Originally Posted by CarAbuser
Just been browsing through some threads about the timing chain rattle issue with the N47 engine and saw a video in one that sounded similar to my engine.
I don't know if it's just paranoia but my engine seems to have a similar sound in the background. It's not there on startup of the car but after the car has been revved the sound then appears.
This is the video of the timing chain rattle I saw posted in one of the threads (this is not my engine):
And this is a video of my engine just now while parked in my garage:
The engine has always sounded like that, I just assumed it was a pump making the noise.
If it is the dreaded timing chain rattle then I will probably opt to chop it in for another E92 rather than pay the £2000 repair when it snaps!
Interested to hear from other 320d owners, if everyone elses engine sounds like that then it will put my mind at rest.
If that is the exact noise as yours, it is coming from the timing chain.
Mine, a September 2008 and at 130k has just been in to have the timing chains, sprockets & guides replaced. At first, at 100k I thought I had picked up a grain of sand in one of the groves of the drive belt as the noise was slower than engine revs. I removed the belt and ran up the engine for a minute but the noise was still there. I realised it was coming from the timing area as the timing of the noise was at audible at about 1/10th of engine rpm. Indicating a chain link or gear tooth problem. I could have timed the noise and then divided it into engine rpm and narrowed it down to a chain or gear.
Anyway when it was pulled down the only noticable item was that the cam chain had a slightly stiff link. It looked like new with no stretch. The gears were like new. The guides had about 0.25mm wear if that, just a scuff.
I had expected lots of wear and stretch as I also had an oil analysis done indicating something wearing prematurely.
The noise must be amplified by the aluminium case.
It almost feels like it was pulled down for nothing, but it had to, as it could have had a cracked chain link ready to snap etc...
Anyway it is all fixed now and cruising.
All the best with yours