OK some notes: - The small tank is purely for intercooler coolant and does not go to the turbo. If you lost this coolant it means the intercooler was not very effective, the intake air was hotter i.e. less dense, and you likely had reduced power. - Whistling noise from turbo could be from louder induction (e.g. from high-flow air filter or intake resonator delete), but again the turbo would have nothing to do with empty intercooler coolant expansion tank. The circuits are independent of each other. - The buzzing noises when unlocking is the fuel system getting primed and ready to start the engine. Buzzing noises after driving and locking can be the auxiliary electrical coolant pump continuing to work (now that the main engine driven coolant pump has stopped) to drive coolant through the turbo to continue to cool it without engine running. Both noises are normal. - There is no coolant level sensor in the intercooler coolant expansion tank, so you won't get a low coolant warning, hence it is possible to have empty tank without knowing it. This has been reported by other B58 owners. - You should add coolant (50/50 mix of anti-freeze and distilled water) up to max level, and monitor the level periodically, e.g. start with after one day, then after two days, then after a week and then after a month. Top it off with coolant if found lower than max after the first day and second day checks, it doesn't necessarily mean coolant is lost, just air escaping. If you continue to need to top up after one week it could mean you have a leak. - Above assumes you will add only abit of coolant to refil the expansion tank to max, and it won't be necessary to bleed the system. There is a bleeding procedure to remove air from the circuit. If you have an empty circuit (not just empty tank) it means you have a leak somewhere. - It is a commonly reported occurrence from B58 owners, for coolant to escape from either expansion tank due to the cap not sealing correctly. If you can see white deposits around the cap, this is a sign of the coolant leaking out from the cap. For peace of mind, you could order a new cap. - If you continue to see coolant loss from the expansion tank, without any clear evidence where it is going, consider taking car for pressure check of the system. The system will be pressurized with external tool, and left for a few hours to see if it holds pressure. If pressure drops then there is a leak. Hope this helps.

Longevity of the stock engine block and internals may be extended by the mild hybrid system to some degree and under some driving environments. There are many variables I would say. If your engine model is sold with and without the system, as is the case with the B58B30B which comes with and without it, to retrofit the system should be relatively straight forward, it will require replacement of all the components that are different. It will likely be costly, and time consuming and need alot of programming to work.

@@NoBrainerTalk interesting, so the mild hybrid system actually makes it more reliable?

@@AW-gj4ji Longevity and reliability are very different. Reliability is more of a system characteristic. Longevity is more a component characteristic. I would not say that the 48V mild hybrid system makes the engine more reliable.

No, always the BMW anti-freeze must be mixed with water.

The 2025 has the B58tu1 which has this system, the 2025 didn’t get the newer B58tu2 which was introduced into the M340 and M440

⁠@@JPRacing715is the b58tu2 better?

@@JPRacing715nevermind I just seen the video between both of them can we get a part 2 please these videos are very interesting

Gen 1 and Gen 2 are arguably both at the same level for tuning...

It's possible that's true, at least from some perspectives.

Yes, they do.

No data will be lost with this method.

Thank you for your compliment and questions: 1. Wow, what a technical question, and to be honest I don't know. It would make sense for the starter generator to be brushless to give it a longer life, emit less noise, have higher efficiency etc. But you are saying it sounds brushed which might mean BMW went for lower cost option? 2. I believe you are correct that it is alot of force for the belt, and it's likely why the first start of the day is with the conventional 12V starter. The starter generator either keeps the crank in motion when coasting, or starts the engine when everything is already warm and lubricated with oil (i.e. least resistance), so that the 48V system is under the lowest possible mechanical strain. The belt is a different P/N and as you say must be a more robust design due to the aforementioned strain it is subjected to when starting the engine.

It has to be brushless with field orientated control from the electronic drive, also looks like it from the pictures.

In stock form, the 6-port B58TU1 with 382hp (if it also has 48V mild-hybrid assist, which some B58TU1 cars have) is arguably a better performance engine than the 1st gen B58 with 340hp. The 1st gen is simpler and arguably more over-engineered and likely to be more reliable, especially after modifications, than the 2nd gen. Both generations are exceptionally good engines with alot of upgrade potential and it's likely you will be happy with either. It all depends on budget and plans. Of course when buying used you also need the previous owner(s) to have taken care of the engines. Hope this helps...

@NoBrainerTalk Yes thank you. I'm not upgrading anything so I will go with a Gen 1. Yeah The 2019 X3 M40i is alittle cheaper then a 2020 model year. Yup I'm always looking at the car fax to see the oil change intervals. Thanks for your help 👍 👊

Strange, sorry I can't help. Good luck!

Why don't you try it and tell us? :) Nothing is deleted with this method, there is no harm to try it. DON'T TRY IT if your volume down button is also broken, as then you will not have a way to turn on the phone.

No, with this method nothing is deleted.

I guess it's easier to route existing coolant lines in the engine bay to new components, rather than add radiators or heatsinks or other heat dissipation techniques.

Hi, as I understand it, this system only assists the engine in the lower power bands and does not add more peak power. So the peak torque and hp remain unaffected. A dyno run of B58TU1 with and without mild hybrid system should however show different curves I believe.

@@NoBrainerTalk i feel like if i push the car from say 2000rpm in 2nd gear all the way up to redline that the eboost holds until it switches gear, third gear loses the eboost completely. It's a weird system. Thanks for your reply!

@@vandelannoitematthie Interesting. Thank you for sharing.

Unfortunately in that case there does not appear to be a solution other than physical repair.

Yes, this has been reported by various owners, and it seems to occur is colder weather environments. It has been reported in 1st Gen B58 and early production 2nd Gen B58 (i.e. B58TU1). Later production B58TU1 engines seem to have a different upgraded oil pump (which owners are reporting as having all metal internals).

Sorry to hear that, yes the broken volume down button was reported by others. Unfortunately noone has reported a method to start the phone when power and volume down button are both broken, so I believe physical repair is now needed.

@@NoBrainerTalk Yes. When all physical buttons are broken, repair is needed. Today I gave my phone to the repair shop. They said that the gaskets that are between the button on the case and the microswitch fell apart. The phone is 7 years old. I guess this is one of the planned obsolescence phases.

@@Tavda Thank you for sharing.

Sorry to hear that. It's possible the volume down button may be defective also, as reported by others.

As cool as some of these systems are, it just further complicates an electrical system that was complex already. Let’s hope that the German Engineering can make this BS last longer than the warranty period. 😂