BUT incredibly that sound can now be listend from engine bay!!!!! I am sure now it comes from the VANOS / CHAIN TENSIONER area!!!!!!!!!
And that sound can travel right over the engine through firewall! With the stethoscope on header = NO SOUND!
With stehto on chain/vanos area the sound is there!!!!!
Now I changed vanos to beisansystems 1½ ago.... So can it actually be the chain tensioner?????????? Or some other chain component?

If it is something with the chain tensioner, especially if it is the plastic guide you want to check the oil for debris as it can clog the oil pump pickup screen. I'd pull the filter cap to check for any signs of things in there and drain the oil into a clean catch pan to inspect with flashlight. Definitely a first step into diagnosing.

Yeah. I am taking my chances and betting on the tensioner. I have ordered a new one which I get today! I talked to a former BMW mechanic who say that theese are prone to fail when milage becomes high. Mine is at 200.000km / 125.000 miles. So I will change it later and report back/ update thread! .. Im crossing my fingers!

thanks for reading..

Lasse

Are you getting just the tensioner or the chain guide rail as well? I ask because the palstic part of the chain guide rail coming apart is what can cause the most havoc.

#7 in this link.

http://www.realoem.com/bmw/showparts...39&hg=11&fg=25

you know it was actually the upper chain tensioner we changed! We changed it today, what a nightmare.. took 10 hours with lots of frustration!! But we succeeded...


Could it be the lower chain tensioner instead? Is that more prone for failure? And you say number 7 is a bad part? .. To change that tensioner would I then need to remove all from front engine again?????

That's if that is actually the problem... I'd want to be sure before going into a big job like that. And if the plastic guide part came apart the debris would be all up in the oil pan and draining the oil into a clean pan would help show if that was the case.

yeah, I will try some stuff tomorrew. . Dont hope its a valve lifter or something.

but i will continue using a stehoscope and troubleshoot diagnose.. I will also replace a exhaust bracket tomorrow.

I also have the same issue as my wife's E46 and this started to happen a few weeks after I had the transmission oil replaced. It only happens randomly, between 35-60mph or so.