Cooling system DS5

[Cristache39]

Hello,

I’m the happy owner for 3 months of a DS5 2012, 2.0 163hp with an automatic gearbox. I love the car.

But i’ve encountered an issue regarding the cooling system. When i bought the car the water temperature was fluctuating, for example after an 60km ride the water was at 60degrees.
Knowing from a VAG car and confirmed by a few people i’ve changed the thermostat.

Even with the new one the temperature is fluctuating but not that low, it’s with 3 lines above 60degrees (still didn’t figure out the values of a line ). So let’s say between 70 and 80-85.
The garage bleed the air out.
The flaps from radiator were checked and the position was closed, i understood that’s fine.

Can you help me with an advice, what i should check further? The guys told me to leave it like this but i don’t think is a good choice, may affect the DPF regenerations.
Other owners of this cars are saying that this is something normal for this engine, never stays at 90. I don’t know cheers!

[Cristache39]

Any idea helps! Or any links with info.

[PaulC5]

You could do with plugging in a code reader to get actual values of the temperature rather than looking at a gauge.

[Cristache39]

You could do with plugging in a code reader to get actual values of the temperature rather than looking at a gauge.

Hi Paul,

Yes, i forgot to mention that.
So at garage, after they changed the G12 antifreeze with the recommended one G33, they bleed the air out and also completed the antifreeze level after a 20min ride.
Then they connected the Launch app to be sure that the cluster is showing the right info and it does.
The guy heated the car (stationary) to 90 and going to a new ride with the code reader also. The water stayed a few km at 90-91-92 and then dropped at 87 while driving. So we turned back to the garage for further checks at radiator flaps.

Being in close position i’ve been told that maybe is still air in system and i should go up and stay at 90 in a few days.
When i asked again what we should do next i received to answers: leave it like that until summer and still air in the system.
I’m worried about regenerations quality

[PaulC5]

What is the outside temperature, if very low then maybe there is nothing wrong and the low engine temperature is due to that. I once replaced a thermostat on a Saab and on that the temperature would cycle up and down on motorways and it turned out the thermostat I had put in not that long before was faulty. Once replaced the temperature was steady. On another car when it rained the temperature would drop and that was a faulty thermostat not closing enough.

[Cristache39]

What is the outside temperature, if very low then maybe there is nothing wrong and the low engine temperature is due to that. I once replaced a thermostat on a Saab and on that the temperature would cycle up and down on motorways and it turned out the thermostat I had put in not that long before was faulty. Once replaced the temperature was steady. On another car when it rained the temperature would drop and that was a faulty thermostat not closing enough.

I took the car for a ride, outside there are -2 degrees.
After 2km the car started to blew hot air. After 4km the water was at 60 and fluctuated (between let’s say 55-64) for almost 7km. 22km i drove with an average speed of 60km/h and now there are 3lines above 60 reaching the maximum of 75degrees during this ride
When i accelerate or it’s over 1800rpm for a couple of minutes the water increases, going back to cruising then the water drops again . With the NEW thermostat.
I’m going crazy here )

[Cristache39]

I understood that it’s normal to fluctuate like that so i’m going to remain chill
Thanks anyway!

[Cristache39]

Hello,

I'm back with this topic because i'm still in a fog with it. So, my engine temperature is staying while cruising at 74-75 degrees (checked with Lexia).
How it's normal, during load or in traffic is going up around 85-90 and then back to 75.
The consumption for this engine (2.0, 163hp) for me seems to be alright.
- 5.5l driving chill in Drive
- 7-7.5 in Sport Mode
- for 4.5k km where most of them are in the city (busy city) i have an average of 8.4l. So i don't think that there is a problem with consumption.
I read a little bit the documentation from ServiceBox and i got that the optimal temperature should be 85degrees. Also, another owner who changed the thermostat (Mahle producer -1st time) with an original one says that now the temperature stays at 85degrees all the time.

What do you think?

[PaulC5]

You could check at what temperature the top hose starts to get warm when the thermostat starts to open. This will check if the thermostat is opening too soon or is the wrong one.

[Cristache39]

You could check at what temperature the top hose starts to get warm when the thermostat starts to open. This will check if the thermostat is opening too soon or is the wrong one.

Hi Paul,

Ok, i will do that with someone specialized. Thank you!

[PaulC5]

You can do this yourself, just touch the top hose and when it just starts to get warm look at the temperature gauge on the car. A quick look on the autodoc site suggests the thermostat should start to open at 83°C https://www.autodoc.co.uk/gates/7181780

[Cristache39]

You can do this yourself, just touch the top hose and when it just starts to get warm look at the temperature gauge on the car. A quick look on the autodoc site suggests the thermostat should start to open at 83°C https://www.autodoc.co.uk/gates/7181780

Yes, from Mahle producer i saw that opens at the same temperature.
Ok, understood. I'm going to check today. Thanks!

[Cristache39]

You can do this yourself, just touch the top hose and when it just starts to get warm look at the temperature gauge on the car. A quick look on the autodoc site suggests the thermostat should start to open at 83°C https://www.autodoc.co.uk/gates/7181780

Hi Paul, i've finally check what you guided me and i noticed that the top hose (the one from radiator) is warm when the gauge shows 74degrees, the temperature where usually stays.
So appears that is it opening to soon. Needs to be replaced? Or i should do other checks?

[PaulC5]

If the gauge is accurate it suggests the thermostat is faulty. If you remove it you could check it in a pan of water being heated and with a thermometer see how it opens and at what temperature.

[Cristache39]

If the gauge is accurate it suggests the thermostat is faulty. If you remove it you could check it in a pan of water being heated and with a thermometer see how it opens and at what temperature.

Sounds a little complicated for my knowledge.
I think that the thermostat is faulty from factory then, it has 1year on the car and it worked like that since beginning.
I kept postponing it because others owners who had the same car from a longer time told me that it’s normal this lower temperature ( not close to 90degrees). Anyway, i will search if i have any warranty or something in order to mount a new thermostat.

Thank you Paul for your support!