What are signs of timing chain tensioner failure?

[Danial Ma <danialma@xxxxxxxxxxx>]

Hi Everyone,

I started up my E28 M5 this morning and it made a horribly loud clanking, 
clunking noise.  It went away after about 15 seconds so my first thought 
was that the tensioner had bled down overnight and pumped back up.  After 
work, it started up without noise.  I searched the archives but didn't find 
any descriptions of pending tensioner or rail failure.  So what's next?

1. Could it be something else?
2. If it is the tensioner bleeding down, how long do I have before some 
kind of catastrophic failure?
3. My car has 145K .  Should I count my blessings, stop driving it and fix 
it?
4. If I am replacing the tensioner, what are the other natural things to 
replace while the front end of the engine is apart?
5. Alright, give me the bad news.  What are the parts I need, how much and 
what are the best sources?

Thanks in advance and I hope my car starts up without the noise tomorrow.

God bless,

Danial

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