2010 X5M Tapping Noise Please Help

[Vortechys]

Hi Guys,

I'm having a problem with my X5M. I have a tapping noise coming from my engine, which I can't fix, and thought maybe you guy's might have some ideas.

Here is the history. Mileage at 18,256. Yes, very low miles. Updated 12 injectors, new lifters bank 1 and 2. New timing chain tensioners. New exhaust and intake cam adjusters bank 1 and 2. Becker down pipes , all new gaskets at turbo connection and exhaust system connection.
Drained oil looks great, oil filter cut open and examined for metal. None found.
Replaced all vacuum lines with silicone while I had access.

That's it. Engine starts right up and runs perfect...except for the tapping.
I'm at my wits end

I have 2 videos posted on YouTube. Links below.

Any help or ideas would be greatly appreciated.

Thanks Guys.

[Sophisticated Redneck]

My guess would be a bent connecting rod, won't show any metal in the oil but gives a similar sound to a bad bearing. If you do a full compression test you should be able to find the cylinder that is effected and verify with a 90 degree camera borescope that it's not reaching full TDC. Cylinder may show additional signs of wear too.

[Doctor///M]

Timing belt chain guide may be out of place?

[Vortechys]

Originally Posted by Sophisticated Redneck

My guess would be a bent connecting rod, won't show any metal in the oil but gives a similar sound to a bad bearing. If you do a full compression test you should be able to find the cylinder that is effected and verify with a 90 degree camera borescope that it's not reaching full TDC. Cylinder may show additional signs of wear too.

SRN would you happen to know if ISTA has a test for compression?

[Sophisticated Redneck]

Originally Posted by Vortechys

SRN would you happen to know if ISTA has a test for compression?

No compression test in ISTA as there is noway to test that without an actual pressure sensor or gauge attached to each cylinder. If compression is compromised enough, it could register as a misfire and ISTA as well as normal OBD2 scanners can show a misfire counter for each cylinder but normally a bent rod will not cause a far end drop in compression to register as a misfire. No harm In checking the individual misfire counters now though to see if any cylinder stands out.

If it were me, I would purchase a compression tester, automotive stethoscope, and dual camera borescope. Use the stethoscope to narrow down which cylinder it's coming from and finish testing with the compression tester and verify with the borescope. If it turns out to be a rod, it might be possible to repair without pulling the engine as I believe another member did all of his bearings with the engine still in but don't quote me on that. If you spend some time searching the forums you should be able to find his posts I am referencing.

[Vortechys]

Originally Posted by Sophisticated Redneck

No compression test in ISTA as there is noway to test that without an actual pressure sensor or gauge attached to each cylinder. If compression is compromised enough, it could register as a misfire and ISTA as well as normal OBD2 scanners can show a misfire counter for each cylinder but normally a bent rod will not cause a far end drop in compression to register as a misfire. No harm In checking the individual misfire counters now though to see if any cylinder stands out.

If it were me, I would purchase a compression tester, automotive stethoscope, and dual camera borescope. Use the stethoscope to narrow down which cylinder it's coming from and finish testing with the compression tester and verify with the borescope. If it turns out to be a rod, it might be possible to repair without pulling the engine as I believe another member did all of his bearings with the engine still in but don't quote me on that. If you spend some time searching the forums you should be able to find his posts I am referencing.

Thanks for all the information. I really appreciate it.
Another question.
Would a leak down tester work as well a compression tester?

[Sophisticated Redneck]

Originally Posted by Vortechys

Thanks for all the information. I really appreciate it.
Another question.
Would a leak down tester work as well a compression tester?

A leakdown tester will test for any issues with the valves or piston rings/cylinders but it's possible to have a bent rod and still be within spec on a leakdown gauge so that's why a compression tester would be best. A cylinder with a bent rod won't reach top dead center and it's compression value will be off. It won't be a huge difference but it will be noticable.

You could also use a metal rod to measure the TDC depth from the top each piston to the top of the spark plug bore and compare If one is shorter then the rest.