Fan still on for few minutes after ignition is turned off

[norwoodm4]

Very peculiar, I have 2019 M4 F83, last night I turned my car off completely and locked the doors. As I was walking away from the car I noticed that the fan under the hood was still going. I waited a couple of minutes and it wouldn't shut off. I opened hood and the fan was blowing air. I closed the hood and the fan shut off. Anyone else experienced this?? This is the second time this has happened in the last 3 months.

[N8er]

My F80 does the same thing. Not very hot out here either.

[CigarPundit]

100% normal. Don’t worry about it. Let it do it’s thing. It will be fine.

[Alpine_F82]

We’ve all been here. It happens when it’s hot outside or you finally went faster than a Prius. It’s the fans cooling down the turbos. It will adjust as you get harder on the engine. But it’s totally normal.

[dinonz]

That just means you're driving it right. If the fans don't come on after you stop, hand back your man card!

[dallastide]

This is your car letting you know she had fun on the way home

[Clark_Kent]

As others have mentioned it's completely normal. I notice it happens when I push the car really hard and then shut it off.

[uniqueMR]

Welcome to M World

[NashvegasR]

Yep normal !

[CanAutM3]

The S55 engine cooling system is built with independent circuits powered by dedicated electrical water pumps. When the engine is shut down, if the ECU deems necessary, it will keep the turbo cooling circuit running along with the radiator fan to cool the turbo down. This helps prolong turbo bearing life.

[F82///M]

It's normal and if you wanna avoid that from happening, drive it easy for at least 10 minutes before shutting down. Efficient engine mode helps if it's really hot outside.

If it runs over 5000rmp even for a brief moment, like passing someone and engine gets shut down within 5 or so minutes it's gonna happen. It doesn't matter if it was easy driven whole day before that.

[CanAutM3]

Originally Posted by zuna13

It's normal and if you wanna avoid that from happening, drive it easy for at least 10 minutes before shutting down. Efficient engine mode helps if it's really hot outside.

If it runs over 5000rmp even for a brief moment, like passing someone and engine gets shut down within 5 or so minutes it's gonna happen. It doesn't matter if it was easy driven whole day before that.

It’s actually the opposite. The engine is governed at a lower operating temperature in the Sport+ engine setting.

[Srac]

Originally Posted by CanAutM3

It’s actually the opposite. The engine is governed at a lower operating temperature in the Sport+ engine setting.

And it's a drastic difference. Mine is close to 120ºC in Efficient and stays around 95ºC in Sport+.

[F82///M]

Originally Posted by CanAutM3

It’s actually the opposite. The engine is governed at a lower operating temperature in the Sport+ engine setting.

Yes, it's running cooler in Sport+ and if you drive it and shut it off in Sport+, cooling map will try to reach Sport+ desired temperatures keeping the fan and pumps on with the engine off.

Switching to Efficient will raise temperature, open the turbo wastegate so it won't be always spinning (like it does in Sport and Sport+) and without raising RPMs too much in those last 10 minutes of driving, everything will cool down enough and fan and pump won't come on after shutting down the engine.

At least that happens with my car, fan comes on after driving in Sport mode in really hot outside temperature, without pushing it during the drive. If it came home in Efficient mode on the same day, same kind of driving, fan will not come on when parked. It doesn't have to keep everything 20 degrees colder.


I don't like fan running after the engine is off, it doesn't drastically drop battery voltage in those few minutes but still, no need for any extra stress knowing how expensive is the battery when everything can be cooled down normal way.

[NoMoreAudi]

My fan has run for as long as 15+ minutes on my F86 after turning it off. Let it breath!

[icegrill]

All good

[AustinGelbM4]

Originally Posted by zuna13

I don't like fan running after the engine is off, it doesn't drastically drop battery voltage in those few minutes but still, no need for any extra stress knowing how expensive is the battery when everything can be cooled down normal "old school" way.

What exactly do you mean "old school"? If you mean just sitting in car with engine idling to "cool" engine, running oil thru the still spinning turbo bearings to preserve bearings and prevent coking etc or using a turbo timer to accomplish above, current emissions regs would definitely not allow that. You would be wasting a LOT of gas. This system works well.

[F82///M]

Originally Posted by AustinGelbM4

What exactly do you mean "old school"? If you mean just sitting in car with engine idling to "cool" engine, running oil thru the still spinning turbo bearings to preserve bearings and prevent coking etc or using a turbo timer to accomplish above, current emissions regs would definitely not allow that. You would be wasting a LOT of gas. This system works well.

I'm probably using wrong expression, not that much old school

Driving it easy last 10 minutes without going over 2500rpm and not using too high gears which would just add more boost. Same way I warmed it up, not sitting and idling.

Anyways, this fan running deal sounds mostly connected to the wastegate operation and how much of boost was generated in X amount of time before shutting the engine down. Ambient temperature comes as secondary input and all together make perfect and safe combo.

[nbennettksu]

Originally Posted by zuna13

I don't like fan running after the engine is off, it doesn't drastically drop battery voltage in those few minutes but still, no need for any extra stress knowing how expensive is the battery when everything can be cooled down normal "old school" way.

Man, don't you remember the old turbo timers on cars that didn't have turbos, but kits installed? This isnt some jalopy 70's rustang with an iron block that the engine weighs 1/3 of the car that can handle abuse and be turned off with nothing flowing to cool it down.

There is no "old school" way. Its got to be cooled down via van.

[Pauldunlop13]

This only happens to my car, well every time I park it

I am surprised this has only happened a couple of times for you

I work 5 miles from home, so there is no taking it easy for the last 5-10 min for me.

[F82///M]

Originally Posted by nbennettksu

Man, don't you remember the old turbo timers on cars that didn't have turbos, but kits installed? This isnt some jalopy 70's rustang with an iron block that the engine weighs 1/3 of the car that can handle abuse and be turned off with nothing flowing to cool it down.

There is no "old school" way. Its got to be cooled down via van.

By the "old school" way I meant turbo engines before these turbos cooled by coolant and electric pumps. It may look like it was yesterday but it's been at least 13 years (thinking N54) since it's been around.
Compared to the new tech I fwas under impression it can be called old school. 70's is already dinosaur era.

Also like I stated above, it doesn't have to be cooled down via fan. If I'm wrong I'm sure my car would run a fan each time it gets shut down but it doesn't and I can tell when it's gonna happen since it all depends on how it was driven before turning the engine off.

[agentrnge]

95% of the time I drive in sport mode, so cooling is not as aggressive as sport+. I usually flip it into sport+ the last ~2 mins of my drive - while taking it easy, and that seems to be enough to give the car enough time to dump a good dose of heat out before going into the garage. That said I dont and would suggest no one worry at all about the fans running for a few minutes.

Edit: also street driving, as aggressive as really possible, unless its like 130F probably isn't even going to make the cooling system flinch compared to a track day session.