Apologies ahead of time for the vertical video, but a relative of ours may be trading in their 2011 E93 335i as it started making a weird sound in the engine bay. The dealer SA couldn't determine the issue without additional diagnostic charges but had told them that 3 temp sensors aren't getting any readings. I don't know anything about these cars but I would think that this sound and the sensors are separate issues? We may take the car off their hands if it isn't a serious issue; my E36M ownership has been pleasant so far so the thought of another BMW doesn't scare me quiet yet. Anyone have any thoughts on what could be causing this sound? I'm thinking belts or pulleys? The water pump was changed recently for about $2k, I'm assuming thermostat(s) were also done but I haven't seen the invoice.