Excessive noise produced by the fan

[Alvinthebeast]

Recently, after a 30-minute drive, I began to perceive an exceedingly loud fan noise emanating at maximum velocity. At first, I mistakenly believed that the noise was emanating from a bus or a truck, but it is, in fact, originating from my X6 vehicle.
The noise reaches such a high volume that passersby instinctively look back and gaze intently.

Upon conducting a more thorough examination, I have discovered a discernible pattern:

Once the engine temperature exceeds 4 blocks (110 degrees C), the fan immediately begins rotating at its highest speed, emitting a loud noise, and continues to do so for a duration of 5 seconds. It continues to occur several times until the temperature reaches around 3 blocks (90-100 degrees Celsius).

After consulting many mechanics, they unanimously confirmed that this is a typical occurrence.

I find this situation abnormal since I have never encountered such strong fan noise before.
I am speculating if one of my temperature sensors may be malfunctioning.

Alternatively, may a deficiency in coolant be the underlying source of the issue? The amount of coolant in my vehicle is slightly higher than the minimal requirement.

Furthermore, I would like to mention that my warranty has already expired, which is why I am seeking guidance on this forum.

Thank you!

[DivineStripe]

Substitute your water cooling pump. Evidently, it is seeing a gradual decline.

[KARlosfuentes]

If you own the N55, it is common for the electric water pump to malfunction prior to the expiration of the warranty.

[Alvinthebeast]

I appreciate your recommendations.

I had anticipated that there would just be a malfunction with the sensor.
The cost of the electric pump is around $700 Canadian.

The warranty on my product just expired a few months ago.

[DivineStripe]

They are powered by electricity. Operate for roughly 50,000 kilometres, then need a replacement. Your progress is currently proceeding at a sluggish pace. Exercise caution. Eventually, the vehicle may have a full failure while in motion, necessitating the need for towing services and incurring extra expenses. I recommend promptly replacing it while the vehicle is still operable and can be driven to the mechanic.

[Alvinthebeast]

I appreciate your thoughtful recommendation.

Tomorrow, I will take my automobile to the mechanic for an inspection.
I will provide an update here with the information I discover.

[LostintheSea]

Indeed, the water pump on my 335i malfunctioned. The occurrence is inevitable, it is just a question of when. Read: It is certain that it will go out. Replacing the part on the e90 was straightforward, so I am certain that it will be even simpler on the e70. It took me around 45 minutes to replace it after consuming around 8 beers, while the aircraft was airborne. Following the occurrence of the noisy fan, the device enters a state of reduced performance, known as limp mode, every 5 minutes. The absence of coolant flow in your engine will result in significant overheating. Please do the task immediately.

[Alvinthebeast]

Thank you everyone for the provided information!

I brought my automobile to the repair facility and accessed the concealed diagnostic codes.
The code indicated a condition like "Inadequate circulation of coolant into the engine".

Within a span of 4 days, the fan exhibits an increased frequency and earlier onset of spinning at its maximum speed.
On my most recent day of driving, the spinning motion began even before the engine had a chance to heat up, around 2 minutes after starting the drive.

I have now stored the vehicle in the garage, as advised, in anticipation of its imminent departure, which will necessitate the need for towing.

Regarding price, I conducted inquiries and want to provide transparency to anyone who may have a similar issue in the future.

The following prices are sourced straight from the Parts Department of Brian Jessel BMW in Vancouver, Canada, as of 2015:

The cost of the water pump is $630.
The price of the bolt is $17.
The cost of the thermostat is $180.

Auto repair establishments will be eligible for a 15% discount.
I was given an estimate of 3.5 hours for the replacement.

Undoubtedly, this is a project that will cost more than $1000.

[LostintheSea]

Also, put antifreeze in it as well. The amount is $1050.

[Hunger_for_love]

The sound of a bell ringing repeatedly. My electricity supply was disrupted last weekend when I was on my way to work, which was somewhat inconvenient. I arrived tardy for work and subsequently had my automobile to be hauled back to my residence. I am now endeavouring to extract my water pump, however due to the vehicle's all-wheel drive configuration, I am encountering difficulties in removing the pump. I have seen several films, however, all of them only feature vehicles with rear wheel drive. Assistance in any kind would be very appreciated.