[jmons]

Hi all, first post here as I am completely lost after searching high and low. I have a 2012 X3 35i with around 100k miles on it. I was driving home the other day when I randomly got the drivetrain malfunction message on the screen. I didn't think much of it so I parked the car at home and left it overnight. The next morning it wouldn't start - it turns over and then just cranks repeatedly but can't start.

I scanned for codes and got several reporting issues with the supply terminal 15N_2 voltage, intake AND exhaust camshaft sensor error, VANOS solenoid valve error, MAF sensor error...

I checked the battery, it's good. Power distribution module is good. Fuses are all good. The one thing that is unusual is when I start the car in accessory mode, I hear this unusual clicking noise from the engine bay like something is struggling to engage but can't. Perhaps this is related, but I am not sure. Here is a link to a clip showing the noise location. There is an initial click, and then at the 23 second mark there is a series of clicks that sounds like it is struggling with something. This is all happening on its own, after I press the start button to turn on the accessory. https://vimeo.com/919887187?share=copy

Any ideas or has anyone dealt with something similar?

[jmons]

Update, car started briefly but there was a loud rattling/clunking noise with tach all over the place so I immediately shut it off. Any ideas?

[Hellshalfacre]

Sorry for your troubles! First thing to do is pop the oil filter out and check for a "German sparkle party." Hopefully you'll see no metal shavings or anything indicative of major internal issues. What was the last maintenance done on the engine?

[jmons]

Originally Posted by Hellshalfacre

Sorry for your troubles! First thing to do is pop the oil filter out and check for a "German sparkle party." Hopefully you'll see no metal shavings or anything indicative of major internal issues. What was the last maintenance done on the engine?

Nothing in the oil filter, looks normal. The last maintenance done was the valve cover and gasket back in November but it’s been fine since.

[Hellshalfacre]

My next move would be to remove the oil filler cap and check the timing chain for excessive slack with a small pick. If the chain is tight and you have no metal in the filter, those would both be good signs.
Next I would pull the coils and plugs and see if one of the plugs is covered in oil or fuel. If the noise is related to something internal, you should see some kind of evidence on the plug.

EDIT: Just re- read your post and saw yours is a 2012, so the easy timing chain check won't be doable from the oil filler cap. Also, watched the video which I didn't see until now. DISA valve possibly. If the clicking is isolated to the intake side, that would be my guess.

[Hellshalfacre]

https://bimmers.com/blog/bmw-disa-va...fails-and-why/