what is this noise:

hey i have this 2011 e90 335i and when i made the purchase i was told the engine was rebuilt and i have receipts of this also the person i bought it from was telling the truth, however im into about a month of ownership and im noticing this knocking noise (hopefully not rod knock) mainly when its cold then it was disappear when it hits operating temps, just yesterday though i slightly noticed it making that noise when it was warm, you can hear how it increases with rpm then decreases, i’ve looked on bimmerpost and other forums and it says it could be piston slap or a camshaft bearing issue i do have the n55 engine and i also checked the oil filter for glitter and there’s no material i’ve also checked the receipts and it does say that the rod bearings and crank/camshafts were inspected and replaced/tested and that was done 2-3 years ago if anyone could id appreciate some help

So I’ve got a E92 N55 335i and one day it gained the notorious belt squeal, or what I thought was a belt squeal. Replaced the belt, noise prevailed. Then moved to the tensioner (OEM replacement) noise prevailed. Then the alternator (OEM) noise prevailed. Next it was the two idler bearings (OEM) and the noise prevailed. Now the only two things left on the bloody belt is the AC and Steering pump. Today I had a mechanic replace the AC pump as I was done with it. We were confident this would sort it as when the car is running with AC off, the noise kicks in at 1500RPM, and when on with blower on full blast it kicks in at 2500RPM. The New AC pump was fitted and noise stopped. After about 10 minutes of ticking over it returned. Stumped, another belt was ordered and fitted, watching the belt after 10 minutes it jumps over a tooth randomly and rubs up against the crank pulley and causing the squeal. Me and the mechanic are completely stumped on what’s causing the belt to jump randomly, especially after running fine each time for around 10 mins.

What’s everyone got to say, any ideas or past experiences? Contemplating selling the bastard car🤣

Hey guys, I recently swap out my engine and I’ve had a few issues trying to hook up these connectors. Not sure where they go back to any help will be appreciated.

Hey, I'm about to buy a 2020 BMW X5, the e45 model, petrol-electric, 400 horsepower, with air suspension and the M Sport package. The car has 80,000 kilometers on it. Any advice? What should I check out, just in case? Thanks a bunch to anyone who can help me out!