I I believe ibhave spun a bearing in my 07;M35x. I've got a loud knock.for codes. I get P0075 and P0550. For the ABS system I'm getting C1109( nothing new) and C1131. Any ideas?

P0075 is a purely electrical code, it means the Bank1 IVT Solenoid is open or shorted. Most likely open, a short will generally blow the ECM fuse and cook the driver inside the ECM. It does mean the ECM can't control the b1 intake cam phaser, and if your chains have any problem then I'd imagine it could cause some rude noises. P0550 is also electrical, an open or short P/S Pressure Sensor. Did a squirrel or road debris maybe tear up your engine harness?

Not that I'm aware of for the engine harness. How would I go about checking the timing chains? Is the small çover at the front of the bank viable for checking that?

Dunno for sure on an M, I'm a Nissan guy. On a Max you can see enough of the cam chains to tell if they're loosey-goosey, but not much more than that. You can't see enough to tell anything about the main chain or guides.

For the main chain that would affect both banks wouldn't it? This is definitely bank 1 only. I don't suppose you would know if I can drop my oil pan without pulling the motor? I'll start a new post on that to see if I can catch anyone's eye on that

No, sorry, I don't know. Nissan doesn't do anything with the VQ35 mounted longitudinally, and the VQ40's are different. I'm sure one of the M mavens in here can tell you.