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What is this knocking noise?

1.4K views 8 replies 3 participants last post by  ou18  
#1 ·
All,

I am a little anxious about an odd knocking noise that has just started from my engine. Here is a link to the audio https://www.dropbox.com/s/zy0insojxpq55m6/BMW.m4a the audio starts in the engine bay, then moves to the passenger wheel well, then finally in the interior with door open.

I am fairly adept at mechanical work, but I am new to BMW's.

Thanks for all of your help.

1997 740i with 153k. I am unaware of any history.

Thanks!_a_
 
#2 · (Edited)
IT COULD be your timing chain guides failing....

easiest way to see if it is, drop your lower oil pan and look for bits of plastic in it. Also check the oil pump screen, need a pick to get around in there, I pulled chunks out of mine, If you have bits of plastic in the oil, dont drive your car anymore, you could do alot more damage as your timing will get out of whack and cause bigger problems..

You have the m62 non vanos engine in there similar to mine...I had a similar noise. I had found plastic bits in my lower oil pan...Will be a tell tale sign of failing timing guides...

here is a link to a video of what the timing guides sound like when they start going bad, sounds similar. Does the noise speed up when you step on the accelerator...

 
#4 ·
Faboch, he has the same engine as I do, which did not have vanos, or are you saying vanos as a catch all for timing chain guides, etc etc?

Please educate me...;)
 
#7 ·
I thought for a second maybe i was going crazy with my terminology... lol...

Well wild, based on FABOCHs latest post, i would check those spark plugs first, doesnt cost you anything, which is the best fix of them all..

If that isnt it, check that oil for broken bits...