Morning all.

Can anyone shed any light on what the noise in the video below might be caused by?

Its a 2004 Petrol L322 with an LPG conversion.The sound began suddenly while i was driving in some fairly deep snow in Europe last winter. The noise is far more prominent on the driver's side.

http://youtu.be/3AttgfCuAOk

So far, I've checked the coils, changed the PCV and top breather hoses, checked for a vacuum on the dipstick tube which suggests no major leaks, changed the plugs and checked as far as possible for cracks in the exhaust from underneath the car.

Thanks in advance gents.

Timing chain rattle... Caused by a failed timing chain tensioner?

Thanks for the swift response.

The timing chain tensioner is a possibility although the noise seems to almost disappear when the revs are at 1500+. Would this be the case if it were a timing chain issue?

Apologies, Terry I've no idea on that.

I've experience of being afflicted with the VW Golf GTi timing chain tensioner related rattle and when I listened to your sound byte, your petrol engine sounded - to me at least - like a tractor which bore some similarities to the petrol engined GTi sounding like a tractor due to chain rattle and so I raised that as a possible cause for you.

This BMW internet link is related to solving timing chain tensioner related rattle for your spec and other spec BMW engines:
http://www.meeknet.co.uk/e31/E31_Timing_Chain_Tensioner.htm

There is a you tube video of a 540i with timing chain rattle too if you do a search although that rattle sounds crisper, cleaner and more metallic than yours.

Guesswork on my part but if you do some searches on the BMW engine, there are many posts ranging from timing chain to VANOS and the list goes on.

Doubtless someone who knows what they're talking about will be along on this forum to give you a more informed correct indication as to what's going on.

PLD118,

Thanks for the steer and I reckon the timing chain is a good shout. Due to time constraints, i think I'm just going to throw it into a specialist and let them take a look. I'll upload the diagnosis once I have it just in case its of use to anyone else.