Coolant temp low

[Funkystanley]

Hi all.

I know winter is approaching and that the temp here in sunny Sheffield this morning was was bloomin' cold..... enough to see a frost on my windscreen but should my car only get up to a quarter of the operating temp (i'm assuming its 45degrees C) even after an eight mile journey of hill-climbing and 40-50mph speeds? my cars done 109k and had the timing belt kit done at 75k so should hopefully have had a thermostat fitted at the same time.  

Is it generally accepted that they dont warm up quick/to full temp in winter? or might it be worth swapping out the thermostat after 35k miles (since it was last done)? 

[Ootohere]

The coolant should get up to a displayed 90*oC.

The oil might not get much above a displayed 50*oC in 8 miles in cold weather, and not to an 'indicated' 92 *oC in double that.

[gav_is_con]

Is it a manual?

if it’s a DSG. It’s common for the DSG stat to cause this issues. 

[varaderoguy]

I am assuming that the water pump was done at the same time.  Check the header tank level.  If its dropped suddenly, then you've got a waterpump failing.

 

The other thing is the coolant itself.  When was the last time it was done?  Has anybody checked to see what the hygroscopic level of water is inside your coolent recently?  Can you also (whilst you are at it....look at the coolant header tank itself).  If the coolant tank has "mit silikone" on it and the tank is looking gungy, then you need URGENTLY to replace the header tank as the silicon bag maybe failing (which will knacker up your cooling and heating system).

Edited 23 November, 2020 by varaderoguy
spelling and grammer corrected

[Ootohere]

 

Hygroscopic'.  That is when a fluid like brake fluid / diesel can absorb H2o.

Hydroscopic something different.

 

Has the strength of the coolant bee  checked?

[varaderoguy]

5 minutes ago, e-Roottoot said:

Hygroscopic

All fixed - yes, you were right.

The level of water contents in relation to the concentration of the coolant.

[Funkystanley]

51 minutes ago, gav_is_con said:

Is it a manual?

if it’s a DSG. It’s common for the DSG stat to cause this issues. 

Its a manual Gav-is-con

[Funkystanley]

42 minutes ago, e-Roottoot said:

 

Hygroscopic'.  That is when a fluid like brake fluid / diesel can absorb H2o.

Hydroscopic something different.

 

Has the strength of the coolant bee  checked?

I've not checked the strength tbh, but its very pink.....so assuming its got quite a good concentration. I'll invest in a hydrometer and do the check.

[Ootohere]

@Funkystanley

Sorry, i was really referring  generally  & to the post above mine, 'Check the strength / ratio' of summer coolant / anti freeze / rust inhibitor otherwise called 'Coolant'.

Pink is OK, but really never use that of a guarantee of enough protection, but then that is a location location location thing, not that much of a UK issue.

 

You need the bigger issue addressed, what ever that is.

[langers2k]

5 hours ago, Funkystanley said:

had the timing belt kit done at 75k so should hopefully have had a thermostat fitted at the same time

 

The thermostat isn't a service item so I wouldn't expect it to have been replaced with a timing belt

[Phil-E]

I'd say it kind of sounds normal especially if you've got the heaters going.

 

On my journey this morning (around 7km) I got about half way and the temperature guage was around 70 and the oil was around 55c.

 

Usually the guage reaches 90 before the oil temp even registers.

 

But I had the fans blasting more than usual as the screen was a bit listed.

 

Usually I just had it set to 19c and the coolant gets up quicker.

[Ootohere]

@Phil-E It says your car is  a 1.4TSI DSG and the OP's is  1.6TDI CR.(Manual)

Different kettles of fish really even if sat side by side in the same ambient temp and started at the same time and run the same distance.

Coolant & Oil quantities also different.

Edited 23 November, 2020 by e-Roottoot

[mac11irl]

i havnt taken much notice of the time to get to temp tbh i also have the 1.6cr, but i would expect it to be slower in "chilly" weather.

 

irs worth noting though... the temp sensor in a mk1 diesel had 2 outputs - one for the dash, one for ecu. the dash sensor tended to fail, mine didnt display above 70deg unless i was pointing downhill stuck in non moving traffic for a few minutes for months. i dont know if this is the same on on 1.6, but if there nothing else wrong, id say your fine..

[Gissin]

i'd put money on the thermostat starting to fail and opening early - this leads to much longer time for it to get up to operating temp. 

 

take it for a longer run 20+miles  and if it still doesn't get up to temp then you may have another problem but I'd start at the thermostat  

[langers2k]

Just to point out, even if the gauge is reporting 90'C, it doesn't mean the coolant is anywhere near.

 

Many modern cars lie as drivers expect to see a stable temperature. If I remember rightly, the coolant gauge will report 90'C anywhere between 75'C and 105'C. If you really want to know the coolant temperature, you'll need a OBD diagnostic device to see what the ECU is reporting.

 

When my 2.0l CR140 had a cool running issue, I logged a drive before and after the thermostat replacement and it make quite a difference:

 

 

[Funkystanley]

Cool (excuse the pun), thanks for all your responses  guys.   The drive home last night, although not as cold, got the temp gauge up to 90 pretty quickly.....and same again on the drive into work.  I'll keep an eye on it under different circumstances etc.  I think if it does start occurring regularly i'll swap out the 'stat. as even if it was swapped out at the timing belt change 35kmiles is a good distance for an item like that to last without wanting to start packing in.

Can anybody recommend a good OBD tool (not megabucks but not cheap e-bay rubbish) and hydrometer pls? i know theres millions on ebay but rather buy half decent than get crappy results, just for the sake of a few more quid.

Cheers. 

[Octy-noob]

I had this fault last year, temp gauge would never reach 90 even after a long run, it would go up a little sitting in traffic but as soon as you were moving it would drop down to about 45 and stay there. I assumed it was because of the colder weather as a lot of threads described that being common but this was not the case. I changed the coolant temp sensor and the thermostat, both at the same time so I'm not sure exactly which solved it but for the price of the parts it was worth changing both. As langers2k said, I wouldn't have thought the thermostat would have been replaced with the timing belt unless you specifically asked for it to be done. 

[Funkystanley]

2 minutes ago, Octy-noob said:

I had this fault last year, temp gauge would never reach 90 even after a long run, it would go up a little sitting in traffic but as soon as you were moving it would drop down to about 45 and stay there. I assumed it was because of the colder weather as a lot of threads described that being common but this was not the case. I changed the coolant temp sensor and the thermostat, both at the same time so I'm not sure exactly which solved it but for the price of the parts it was worth changing both. As langers2k said, I wouldn't have thought the thermostat would have been replaced with the timing belt unless you specifically asked for it to be done. 

 

[Funkystanley]

Cheers Octy-Noob.  Certainly wont do it any harm swapping the stat anyway, and as you say, for the price of the parts.

I've only just bought the car actually so not sure if this was changed at the time.

Might add a workshop manual to my shopping list of hydrometer and OBD tool 

[Gissin]

3 hours ago, langers2k said:

Just to point out, even if the gauge is reporting 90'C, it doesn't mean the coolant is anywhere near.

 

Many modern cars lie as drivers expect to see a stable temperature. If I remember rightly, the coolant gauge will report 90'C anywhere between 75'C and 105'C. If you really want to know the coolant temperature, you'll need a OBD diagnostic device to see what the ECU is reporting.

 

 

yeah you're spot on , I did some live logging recently and as soon as the coolant hits 76'c it shows 90 on the dash  and when it drops past 74'c you'll start to see the gauge drop on the dash.