Hey guys,

I recently purchased the 997tt, along with a friend of mine. They both have previous owners. It seems to me that everytime I drive my car, after I turn off the engine and lock it, a couple minutes later the fans come on in the engine. It will come on sometimes twice or even three times for 2 minute intervals and then shut off. This kind of worries me, as my buddy's very rarely comes on he says. I can understand once in a while when I really rip the car for them to come on but not almost everytime... and for it to be staying on for that amount of time (or in that many intervals, rather)... Need your feedback... Is this a problem??

Thanks and best regards,

 

Unfortunately, I've only had my car a couple of weeks so I cannot be very definitive in answering you. However, I have noted that my fan comes on, even when the driving is not that spirited. I can't really pinpoint what triggers the fan because my trips are all about the same and the majority of the time the fan stays off.

 

No, that is normal. It's just venting hot air from the engine compartment.

 

it's normal.

 

definitely normal...Turbo engines get HOT.
Also try idling for 30 seconds before turning off ignition.
Not good to shut down immediately after a spirited drive.

Use a "warm down approach" and coast a little before
shutting engine down for long periods.

The fan compensates more for cooling if you do not.

 

Normal....I have an 07 and just last week when I was in for service....there was a recent software update that was specifically for the engine compartment fan....it disabled the low fan speed and now only operates the fan on high speed.....the update is mainly for colder climate cars.....seems they were having problems when ice would build-up on the fan and the low speed was not strong enough to break free the fan from the ice before the engine generated enough heat to melt the ice naturally....the fan motor would burn up on low speed before the ice melted...

Clearly not a problem for me in Florida.

 

Thanks guys.

Only thing weird about it though is that my buddy's doesnt turn on as much as mine...
We've driven a few places together and his fan only came on once, whereas mine has come on every single time we park, and we rip the cars the exact same...

 

He may have the problem....It's normal

 

When it hot out 95+ degrees you don't even have to push the car and the fan will cycle a few times to cool off the turbos. This is a normal thing. Make sure to keep your oil level topped off as the car eats oil as well.

 

Yeah it is normal.. I always wait a little before shutting down and sometimes fan still works..

 

It may not necessarily be normal... you both have similar cars and you say yours runs more than his does.... make sure your engine compartment temperature sensor hasnt fallen out of its holder and is resting down closer to the exhaust where temperatures are going to be higher that where it is mounted usually...its located between the first two intake manifold runners on your passenger side of the engine. there is a U-shaped notch in between the runners where it is mounted feel for it with your hand.. if its not there feel below it to see if it has fallen down.... just make sure the engine is cold obviously.....

Kyle.

 

This is even less of an issue on the 997 Turbo due to the water cooled turbos. Not saying its a bad idea, just not as needed as on oil-only turbos. Quote from 997 turbo techincal book...
"For the first time, the bearing housings of the turbochargers are additionally cooled with water on the new 911 turbo. This is carried out by means of a separate electrically operated water pump. This pump increases the water throughput according to requirements at low engine speeds and even enables efficient cooling of the heavily stresses turbochargers when the engine is stationary after journeys which have made great demands of the engine"