SQ5 3.0 TDI Coolant Temp

wilco184

Registered User
Hi,

For cars with the 3.0 TDI engine, what does your coolant temperature gauge display when the ambient air temperature is 15 Deg C or above?

I have an issue where below 15 Deg C, the coolant temp gauge sits at 90 and is steady which is fine, but at 15 or above, the gauge fluctuates down to 75 and wanders slightly.

Please let me know if this is normal or if I have an issue. Car is a 2013 SQ5.

Many thanks,

Matt.
 

-Ju-

Well-Known Member
VCDS Map User
I dont remember mine being anywhere but up to 90 and staying there tbh.
It'll be a while before I can check it though.
Its a 2015 SQ5
 

45bvtc

The Older I Get The Better I Was
Supporter
Gold Supporter
Ours, a 2016 SQ5, quickly rises and stays at 90ºC whatever the ambient air temp

Stay safe you guys... :yes:
 

SteveMcB

Registered User
Yep, steady 90 is what it should be running at, my 3.0tdi cabby is the same.
 

wilco184

Registered User
Thanks for the help all.

The car needs approximately 10 miles of normal driving to warm up to 90 when the ambient is less than 15 Deg C, which does seem a little long.

Thanks,

Matt.
 

45bvtc

The Older I Get The Better I Was
Supporter
Gold Supporter
Thanks for the help all.

The car needs approximately 10 miles of normal driving to warm up to 90 when the ambient is less than 15 Deg C, which does seem a little long.

Thanks,

Matt.

Mine takes less than 5-miles, Matt, whatever the ambient temp; maybe you should look at the thermostat as that seems rather lazy and/or not closing properly.
 

wilco184

Registered User
I think I've narrowed the fault down to the 'coolant regulator valve' which I don't think is closing. It's supposed to cut the circulation of coolant in the block and regulate it at 105 Deg C. The point of this is quicker warm up apparently.

I've had a look at the valve with a borescope and the linkage doesn't appear damaged. I've bypassed the solenoid controlling this valve to make the valve permanently closed and the block temperature didn't increase higher than the normal coolant temperature which isn't right.

To help prove this valve is broken before I replace it as it's quite labour intensive, please would anyone be able to check their car with VCDS? Specifically, the measuring block value 'IDE03582 - temperature sensor for engine temperature management' with the gauge temperature at 90 Deg C please? I think my car should be showing a higher temperature here than the normal coolant temp, but it doesn't.

Many thanks,

Matt. :)
 

-Ju-

Well-Known Member
VCDS Map User
I think I've narrowed the fault down to the 'coolant regulator valve' which I don't think is closing. It's supposed to cut the circulation of coolant in the block and regulate it at 105 Deg C. The point of this is quicker warm up apparently.

I've had a look at the valve with a borescope and the linkage doesn't appear damaged. I've bypassed the solenoid controlling this valve to make the valve permanently closed and the block temperature didn't increase higher than the normal coolant temperature which isn't right.

To help prove this valve is broken before I replace it as it's quite labour intensive, please would anyone be able to check their car with VCDS? Specifically, the measuring block value 'IDE03582 - temperature sensor for engine temperature management' with the gauge temperature at 90 Deg C please? I think my car should be showing a higher temperature here than the normal coolant temp, but it doesn't.

Many thanks,

Matt. :)
Not sure when I'll be able to but if nobody else does in the meantime, I'll check it once lockdown is over

Sent from my SM-N960F using Tapatalk
 

-Ju-

Well-Known Member
VCDS Map User
So I thought it would be a good idea to at least run the car up to full temperature and get a bit of charge in the battery.
So bear in mind its not had an actual run, it's just sat there and built up to 90 and stayed there for 5 minutes.
This is what its showing.
The 3rd one is the value you requested and it has slowly built up to that, it is still climbing albeit very slowly.
I'll try it again once it has a proper rum and see where it's at.
20200505_200731_copy_2268x3024.jpg
 

Jay926

Registered User
After reading these posts, my SQ5 TDI temperature took a while to get too 90 today, was hovering around 90 then dropped slightly and increased back up to 90 until I hit the carriageway where it stayed steady at 90 again... so I will keep an eye on it, try to gauge my driving time and miles to see how long it takes to steady out at the correct temperature.... I’m guessing, that it’s suppose to hit 90 and stay there, regardless of driving style, ambient temperature etc etc?
 

45bvtc

The Older I Get The Better I Was
Supporter
Gold Supporter
I’m guessing, that it’s suppose to hit 90 and stay there, regardless of driving style, ambient temperature etc etc?

Yes, that is what it should do and for sure it is controlled by the engine coolant temperature thermostat which, in your case, appears NOT to be closing correctly; if partially OPEN as I suspect then that would cause the engine temp to rise slowly (coolant by-passing the engine (heat source) and running through the (coolant) radiator) and again drop slowly (again by-passing the heat source) if and when the engine isn't being 'worked' sufficiently to generate heat - both of which you report.

As you are not reporting coolant loss only coolant temperature control then for sure I would get that thermostat replaced.
 
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