Cooling fan on after start and drive when engine cold ?

[RUBYBLACK]

Good evening any and everyone.
I wonder if any advice direction could be offered.
I have a 2008 e86 N52 3.0 si I've owned it since 2018 and covered 30,000+ miles relatively trouble free.
Since Tuesday ( so for past two days) 2 mins approx after starting and driving from cold, the cooling fan runs at maximum speed ? and only cuts out ironically when it reaches Normal op temp. (outside temp is about 6-8 O.c) .In the years I've had the car it's never over heated and the temp needle sits there mid point, come Sun or snow. The issue is I assume? only causing electrical load and slightly lowered fuel economy, I'm still managing 36.6 mpg as it has since the day I got the car.
I've searched CTS, fan relays? and wiring and wondered which order to attack first? Could I please ask if anyone has had a similar issue/ fault and hence offer any direction? and any advice/ help will be greatly appreciated
never demanded.
Thank you
Kevin B

 

[RUBYBLACK]

Sorry I should have also mentioned....NO dashboard warning light or error codes on impa or hand held reader.

 

[Argyll Andy]

Hi Kevin, fans running from cold on an N52 normally indicates a failing water pump.

Have a look art this thread and see if anything is familiar. I know you say yours showing codes but maybe try with a different reader? HTH

https://z4-forum.com/forum/viewtopic.php?t=133163&hilit=Water+pump

 

[RUBYBLACK]

Good evening Andy, thank you for your swift reply and the failing pump thread, greatly appreciated.
I've had a read through the related posts to the thread, they all seem to mention erratic temperature and fan runs immediately from
cold start mine cuts in after two minutes or maybe a mile of sympathetic driving and then cuts off at normal temp as mentioned and isn't heard again on the journey? my temp gauge rises steadily to vertical/ mid way and doesn't falter even in traffic or when/if gunning it. ( within national speed limits oc)
Would not the code be visible in impa ? I have run the water pump via impa at all the % rates of speed, the increase/decrease is apparent with both noise and flow visible in the rad filler neck, it also sounds sweet, not rough or noisy ?.
Wouldn't you believe it though, today on my return from work....nothing ? the only difference was ambient outside temp of 10.oC ish.
I plan to tinker at weekend unplug anything temp related, clean contacts and disconnect battery/ hard reset ecu.
I'll come back whether I find anything or not
Thanks again
Kevin B.

 

[HazArc]

Good evening Andy, thank you for your swift reply and the failing pump thread, greatly appreciated.
I've had a read through the related posts to the thread, they all seem to mention erratic temperature and fan runs immediately from
cold start mine cuts in after two minutes or maybe a mile of sympathetic driving and then cuts off at normal temp as mentioned and isn't heard again on the journey? my temp gauge rises steadily to vertical/ mid way and doesn't falter even in traffic or when/if gunning it. ( within national speed limits oc)
Would not the code be visible in impa ? I have run the water pump via impa at all the % rates of speed, the increase/decrease is apparent with both noise and flow visible in the rad filler neck, it also sounds sweet, not rough or noisy ?.
Wouldn't you believe it though, today on my return from work....nothing ? the only difference was ambient outside temp of 10.oC ish.
I plan to tinker at weekend unplug anything temp related, clean contacts and disconnect battery/ hard reset ecu.
I'll come back whether I find anything or not
Thanks again
Kevin B.

I know this was a while ago, but what was the outcome of this? Noticed my fan has started to come on shortly after starting the engine even when it's 2 degrees outside!

 

[enuff_zed]

Good evening Andy, thank you for your swift reply and the failing pump thread, greatly appreciated.
I've had a read through the related posts to the thread, they all seem to mention erratic temperature and fan runs immediately from
cold start mine cuts in after two minutes or maybe a mile of sympathetic driving and then cuts off at normal temp as mentioned and isn't heard again on the journey? my temp gauge rises steadily to vertical/ mid way and doesn't falter even in traffic or when/if gunning it. ( within national speed limits oc)
Would not the code be visible in impa ? I have run the water pump via impa at all the % rates of speed, the increase/decrease is apparent with both noise and flow visible in the rad filler neck, it also sounds sweet, not rough or noisy ?.
Wouldn't you believe it though, today on my return from work....nothing ? the only difference was ambient outside temp of 10.oC ish.
I plan to tinker at weekend unplug anything temp related, clean contacts and disconnect battery/ hard reset ecu.
I'll come back whether I find anything or not
Thanks again
Kevin B.

I know this was a while ago, but what was the outcome of this? Noticed my fan has started to come on shortly after starting the engine even when it's 2 degrees outside!

Pretty sure it’ll be the first sign of a failing water pump. If it fails completely you only have a very short distance before it overheats.
I would suggest you don’t use the car and get the pump changed.
If you can do it yourself it’s a couple of hours in total.
Be sure to get a genuine Pierburg pump and new thermostat. Should be around £300.

 

[HazArc]

Good evening Andy, thank you for your swift reply and the failing pump thread, greatly appreciated.
I've had a read through the related posts to the thread, they all seem to mention erratic temperature and fan runs immediately from
cold start mine cuts in after two minutes or maybe a mile of sympathetic driving and then cuts off at normal temp as mentioned and isn't heard again on the journey? my temp gauge rises steadily to vertical/ mid way and doesn't falter even in traffic or when/if gunning it. ( within national speed limits oc)
Would not the code be visible in impa ? I have run the water pump via impa at all the % rates of speed, the increase/decrease is apparent with both noise and flow visible in the rad filler neck, it also sounds sweet, not rough or noisy ?.
Wouldn't you believe it though, today on my return from work....nothing ? the only difference was ambient outside temp of 10.oC ish.
I plan to tinker at weekend unplug anything temp related, clean contacts and disconnect battery/ hard reset ecu.
I'll come back whether I find anything or not
Thanks again
Kevin B.

I know this was a while ago, but what was the outcome of this? Noticed my fan has started to come on shortly after starting the engine even when it's 2 degrees outside!

Pretty sure it’ll be the first sign of a failing water pump. If it fails completely you only have a very short distance before it overheats.
I would suggest you don’t use the car and get the pump changed.
If you can do it yourself it’s a couple of hours in total.
Be sure to get a genuine Pierburg pump and new thermostat. Should be around £300.

Thanks for that. Is this something that would flag up with a code reader?
Nice avatar pic too :wink:

 

[enuff_zed]

I know this was a while ago, but what was the outcome of this? Noticed my fan has started to come on shortly after starting the engine even when it's 2 degrees outside!

Pretty sure it’ll be the first sign of a failing water pump. If it fails completely you only have a very short distance before it overheats.
I would suggest you don’t use the car and get the pump changed.
If you can do it yourself it’s a couple of hours in total.
Be sure to get a genuine Pierburg pump and new thermostat. Should be around £300.

Thanks for that. Is this something that would flag up with a code reader?
Nice avatar pic too :wink:

Cheers. The photo is the actual jet I was lucky enough to get a back seat trip in many years ago.

I recently changed a water pump for someone with exactly your symptoms. When I plugged in my Autophix code reader it gave me three separate codes within the engine management (DME) section, all relating to the water pump and wrong information being sent from it.
Sorry but i cannot remember what the codes were.

 

[HazArc]

Nice! Never had a backseat ride in a fast jet, but get plenty with the larger fleet!!!
Is it a difficult job to replace the water pump? Can it be done from axle stands or does it need to be up on a ramp? Car is going in to a BMW specialist in Swansea soon and I’m wondering if it’s worth getting him to replace the pump.

 

[enuff_zed]

Nice! Never had a backseat ride in a fast jet, but get plenty with the larger fleet!!!
Is it a difficult job to replace the water pump? Can it be done from axle stands or does it need to be up on a ramp? Car is going in to a BMW specialist in Swansea soon and I’m wondering if it’s worth getting him to replace the pump.

Replace the pump AND thermostat.
I usually run the front of the car up on ramps to get access as you do the job from underneath. I always make sure the heater is set to fully hot first, then leave the front end up on ramps while I run the bleed procedure, just to be sure there is no air trapped.