BMW M5 Forum and M6 Forums banner

1 - 9 of 9 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter #1
Hey everyone my m5 started making this ticking/knocking sound I cant seem to identify. Started after high rpm in 3rd gear car has 101k. I replaced the timing chain tensioner on the left side issues didnt change. No codes and it dosen't seem to have power loss. Car didnt go above 2k rpm in video noise loaduiest at 1.5k in video.

 

·
Registered
Joined
·
116 Posts
Possibly could be timing chain or rod bearing. But it almost sounds like an exhaust manifold leak too. Check around there first before digging deeper.

Sent from Uranus with Love.
 

·
Registered
Joined
·
240 Posts
This is where some sound analysis software would be helpful, and unfortunately I am not an expert in that. The two most likely causes are rod knock or lifter tick. Hard to tell from the video, but rod knock would be at the frequency of crank rotation and lifter tick at half of that frequency. If anyone can analyze the sound file then this may answer the question.
 

·
Registered
Joined
·
2,452 Posts
IMO that is not what lifter tick sounds like. I would drain the oil, probably send a sample to Blackstone, drop the pan and see what you find.
 

·
Registered
Joined
·
9,924 Posts
Pull the valve cover off that bank and don't start the car again. Might be a totally collapsed lifter, very rare on these cars. Could be the cam chain tensioner failed, or maybe the spring clip that holds the vanos pump in place is half off and smacking something? If you remove the cover it will probably be self evident. Running the car is just going to make things worse, so don't do that. It could also be the timing chain but they don't really sound like that, but that is videos, they change things. If you don't see anything up top drain the oil and pull the lower pan looking for plastic bits that were once the chain guides.
 

·
Registered
Joined
·
206 Posts
You may want to run a compression check. Not to alarm you but I had an intake valve collision on my 01 about 2 years ago (appx the same mileage). An uncanny resemblance in terms of how I remember it sounding. Most of all, good luck. Hope it turns out to be simple.
 

·
Registered
Joined
·
12,804 Posts
That does not sound good. Broken rocker arm?

I would NOT run the engine until you get some help on diagnosis. Right now it is still running, so damage is not excessive....YET.

Regards,
Jerry
 
1 - 9 of 9 Posts
Top