X6M electric fan runs always after stop

[Lighting.Grey]

Is it normal that the fan do not run after the drive? Everyone's fan alway running after the drive??

[silentm]

Fans have to run after you turn off the car. This is a safety feature BMW and I believe Porsche has as well.

Propose is that after running a turbo car (hard or regular) turbo internals get extremely hot. If you turn them off right away without going through a cooling cycle, like parking and running the car for 5-10 minutes before shut off, The turbo internals can seize, melt, not function at all.

So engineers programmed the ecu to do this cause they know not all drivers will let the car idle after use before turning it off.

Same goes when for cold start, but I don't think it's long enough. Unfortunately, new breed of BMW owners don't care because they don't keep the car long enough. Typically most issues related to not treating a car properly is owned by the 2nd or 3rd owner when car is out of warranty, hence most don't ever hear about it.

I am generalizing based on what I've seen in SoCal, other places might be different, however I doubt it.

[Lighting.Grey]

Originally Posted by silentm

Fans have to run after you turn off the car. This is a safety feature BMW and I believe Porsche has as well.

Propose is that after running a turbo car (hard or regular) turbo internals get extremely hot. If you turn them off right away without going through a cooling cycle, like parking and running the car for 5-10 minutes before shut off, The turbo internals can seize, melt, not function at all.

So engineers programmed the ecu to do this cause they know not all drivers will let the car idle after use before turning it off.

Same goes when for cold start, but I don't think it's long enough. Unfortunately, new breed of BMW owners don't care because they don't keep the car long enough. Typically most issues related to not treating a car properly is owned by the 2nd or 3rd owner when car is out of warranty, hence most don't ever hear about it.

I am generalizing based on what I've seen in SoCal, other places might be different, however I doubt it.

Thanks for sharing the info, still wondering if I should book a appointment to check it out, my fan sometime doesn't run after the drive.

[NikNala]

Here's an extract from an industry paper on turbocharger oil engine oil coking. The same thing happens in aircraft turbine engines so most turbine engines have a two minute idle cool down on shutdown for the same reason.

"'Coking' of the Engine Oil – The critical point affecting both the oil and the turbocharger arrives when the engine is shut off after the
turbocharger has been under rigorous use
for some period of engine operation. At this
point, the oil no longer circulates through the shaft bearings to carry away the heat. Consequently, the full heat of the turbocharger shaft is imposed on the bearing area and the relatively small volume of oil in the bearings and galleys immediately adjacent as shown in Fig. 2.
At these temperatures, the oil seems to
respond much differently than at the much
lower temperatures experienced in the
engine. Depending on oil formulation and
the extent of its usage in the engine and
turbocharger, oxidation of the engine oil in
the turbocharger may form a hard, somewhat porous, coke-like carbonaceous mass in the galleys. In time, this coke formation plugs the galleys as shown in Figure 2 causing failure."

[notyourdadsf86]

Originally Posted by dsaare

Thanks for the feedback.
1. Did you buy only 2 wheels for the back or you bought 4 more only 285 all around?
2. It's a funny feeling since i did not have a car that did that, yet. No Mercedes does that (to my knowledge) even the twin turbo ones. Every time i leave the car in the garage and that fan kicks in to cool off the turbos, i feel like it's gonna catch on fire ))
3. I need a stock exhaust i think. Where do i find someone thats looking for an upgrade?

Where are you located? I have a full OEM catback system, since I swapped the whole thing.