Porsche 997 engine fan on all the time

[scottydog1979]

Hi ive got a 2005 carrera s 997, ive owned the car for around 7 months, I noticed a couple of weeks ago that the engine fan was running when I returned home after a short trip to the shops, from this point onwards I started monitoring it and have found that once the water temp hits dead centre and the oil temp gets to 90 degrees the rear fan comes on and then wont go off at all during that day even if you leave the car for a couple of hours to cool it still comes on when you start the car, the temperature gages don't really move at all so I don't think its over heating, the only time it doesn't come on straight away is if its been stood over night, ive changed the temp sensor located in the engine compartment but its still the same, can anyone offer any advice or should I take it straight to the garage ?

[Paul O]

Mine does this also. I asked the question and was told its normal for the fan to be on at lot.

If you have a neb in the engine bay, there ain't a lot of room in there so I guess it makes sense to have artificial cooling going on.

[scottydog1979]

Thanks for the info Paul, maybe its just that i havnt noticed it being on before then.

[sportsandclassic]

Not really heard 997 engine bay fans coming on as much as 996 ones. Its better its on than off! Does it stay on all the time when left or does it cycle itsellf ?

[scottydog1979]

its never come on when i turn turn the ignition off, its just on constant when the engine 1st gets upto temp in the morning after its been stood all night, it doesnt come on for a while then go off for a while and so on like i thought it would ?

[rob.kellock]

My Spyder displayed similar symptoms with fan at front offside. OPC replaced the unit (apparently the controller was an integral part) under warranty and normal service was resumed.
Mine was coming on from stone cold though.

[anonymous-user]

Are you talking about the engine bay fan - which removes hot air from engine bay - or the fans in the front wheelarches?
Former often works and is not controlled by coolant temp.

[scottydog1979]

Its the engine bay fan.

[MadMark911]

OK - the engine bay fan on my C2S only came on when the car had been sitting in traffic for some time, or after a fast run when the oil temp was over 95 degrees! When left for a couple of hours and restarted, it didn't come on again until it was hot. In my opinion, you might want to get it checked ....

[Steve Baker]

scottydog1979 said:

Hi ive got a 2005 carrera s 997, ive owned the car for around 7 months, I noticed a couple of weeks ago that the engine fan was running when I returned home after a short trip to the shops, from this point onwards I started monitoring it and have found that once the water temp hits dead centre and the oil temp gets to 90 degrees the rear fan comes on and then wont go off at all during that day even if you leave the car for a couple of hours to cool it still comes on when you start the car, the temperature gages don't really move at all so I don't think its over heating, the only time it doesn't come on straight away is if its been stood over night, ive changed the temp sensor located in the engine compartment but its still the same, can anyone offer any advice or should I take it straight to the garage ?

Not sure if this is relevant to your issue but there was a recall 'W737' 'Deactivation of speed setting 1 of engine compartment blower'

[huytonman]

Sounds like the same problem as my old car, it's not normal and does require a fix, that said it shouldn't do much harm as it is but the noise irritated the hell out of me...

[scottydog1979]

its had the recall to stop the fan coming on at low speed all the time ( i think all they do is pull the fuse and put a blank in there ) but its on full speed now,

[scottydog1979]

huytonman said:

Sounds like the same problem as my old car, it's not normal and does require a fix, that said it shouldn't do much harm as it is but the noise irritated the hell out of me...

What was the problem with your old car huytonman ?

[scottydog1979]

Ok, so I took the car to my local Porsche specialist to take at look at it, he's told me he's checked the car over and theres nothing wrong with it and its perfectly normal for the fan to come on when it reaches full running temperature, said he got another 997 same year there and that was exactly the same. ??

[davek_964]

Just out of interest - is it normal for the water temp to hit "dead center" on 997s? I've never had a car where the water temp would get to the center of the scale (assuming that's what you meant) - usually, they hover at about 1/3rd.

[MadMark911]

davek_964 said:

Just out of interest - is it normal for the water temp to hit "dead center" on 997s? I've never had a car where the water temp would get to the center of the scale (assuming that's what you meant) - usually, they hover at about 1/3rd.

Yup - should show a "normalised" 80 Degrees!

[GuitarPlayer63]

^ +1

80 is dead centre on the dial, the oil temp sits about a 1/3rd of the way up the scale

[scottydog1979]

Can anyone tell me where the relay is for the rear fan please ? ive been told this may be the cause of the problem.

[Snozzer]

My front fan was on all the time. The OPC had a look - There are two fans at the front and there was a stone stuck in the blades of one. Just a thought!

[Raitzi]

Thermostat might be broken but likely not. Though it would be very clever from porsche to have fans constantly on when thermostat fails compared to that fans off in same situation.