[Majid Yasin]

Hi
I have a 2012 CC 140PS DSG

I am from uk having the same problem. Looking to change the thermostat for the dsg. Problem is nobody knows what i am talking about. Can someone please tell me where is this located??. Helpp please.. already changed coolant sensor and thermostat near water pump.

Thank you
Maji

 

[Passatoli]

Hi
I have a 2012 CC 140PS DSG

I am from uk having the same problem. Looking to change the thermostat for the dsg. Problem is nobody knows what i am talking about. Can someone please tell me where is this located??. Helpp please.. already changed coolant sensor and thermostat near water pump.

Thank you
Maji

I had this problem and was quoted $600 AU to fix it, looked on this site and found out about the DSG thermostat, went to VW parts dealer, they couldn’t even find it listed - have them this number 1K0121113A
They ordered it in for me.

Pretty easy job to do and the engine now gets quickly up to temp.

Good luck

 

[bentas1]

Great to hear you’ve fixed the problem without having to spend $600. I’m amazed that mechanics working on VW are not familiar the second thermostat and keep recommending to change the primary thermostat.

 

[Passatoli]

Great to hear you’ve fixed the problem without having to spend $600. I’m amazed that mechanics working on VW are not familiar the second thermostat and keep recommending to change the primary thermostat.

I was surprised when the parts guys couldn't work out what I was talking about too, having that part number was gold!

 

[Johnc]

I have the same problem with two Mk6 Golfs, both manual trans. I paid $500 to have thermostat replaced in one (CBAB) and it made little to no difference, clearly its not the DSG thermostat! Problem is not quite as bad as others have described, but in low stress driving in cool weather neither car gets to temp. Any thoughts?

 

[Passatoli]

I have the same problem with two Mk6 Golfs, both manual trans. I paid $500 to have thermostat replaced in one (CBAB) and it made little to no difference, clearly its not the DSG thermostat! Problem is not quite as bad as others have described, but in low stress driving in cool weather neither car gets to temp. Any thoughts?

With the right tools, the DSG thermostat could be replaced in 20 min.
The main thermostat is behind the alternator, this is a big job, maybe 3 hrs or so.
Are you sure it was the former as $500 would be a rip-off?

 

[greeceq5]

be aware that my 2.0 Tdi CAHA 170 has in addition to the main, 2!!! more in line thermostats 1K0 121 113 A. The first is in a hose returning coolant from the egr cooler to the radiator and the second in a hose from the oil cooler to the radiator. There is also a non return valve 1J0122351 in a hose bypassing the first in line thermostat coming from the egr cooler. It took me 2 months and 3 main thermostat changes to discover the 2 in line thermostats which were both bad and fix my underheating issue after changing them both. They are no 11 and 15. 3 is egr cooler and 2 is oil cooler.

I first discovered and changed no 15 and still nothing changed and the car was undercooiling although maybe not that badly. When I changed no 11 though everything come back to normal operations. They are quite easy to check too. When you remove them just blow through the hose. Good ones just barely let air go through and bad ones let it go freely.

when checking advanced measuring values with vcds if all thermostats are good the coolant temperature and coolant temperature at radiator outlet rise from cold with a big differenence in value, at least 30c. This is normal and coolant temperature goes up first. When my 11 was bad the 2 temperatures were rising together with practically no difference at all!!
So I suggest to anyone with a cold engine situation to diagnose with VCDS and then search for the in line thermostats. Dont rely on etka diagrams. Mine was just showing a hose no 23 and it was missing the oil coolant one completely!!!

Search all 20mm hoses by hand as some thermostat may be hiding somewhere.

 

[Johnc]

As I said they are both manuals, so can't possibly be the DSG thermostat . The $500 seemed a ripoff until I found out how much work was involved, however still a waste of $ as it made no difference.

 

[notGotTheDream]

I have the same problem with two Mk6 Golfs, both manual trans. I paid $500 to have thermostat replaced in one (CBAB) and it made little to no difference, clearly its not the DSG thermostat! Problem is not quite as bad as others have described, but in low stress driving in cool weather neither car gets to temp. Any thoughts?

Yes you have two manuals, but then so does every DSG owner. The DSG is NOT an automatic transmission. The DSG is a "computer controlled" manual transmission, with a dual shaft (gears split odd and even with dual clutch) system.

So what is referred to above as the "DSG" thermostat is actually a manual gearbox cooling system (aka heat exchanger) thermostat.

So while your car may not have a dual clutch gear box cooling system, it may have another thermostat elsewhere playing havoc.

I have the same issue.

Other problems:

If you have the pump in the fuel tank replaced, the fuel lines in my model are either the same size (supply/return) or so close that a semi-trained grease monkey can connect them reversed (they might even be so lazy when they realise and swap the ones in the engine bay to counter the mistake). If during later engine bay work it gets corrected, you will have low fuel pressure issues during acceleration (mostly when fuel level is below half).

If someone removes the engine cover without replacing it, you will hear injector operation noise.

 

[Keithuk]

notGotTheDream

First posts normally go in introductions else you could get a free fix and we never see you again!!!

Forum Rules and Guidelines

Any problems search TDI Wiki as that covers write ups and forum posts.

On my Golf GTD the fuel pump in the tank runs for a couple of seconds when you turn the ignition on, to prime the fuel system.

 

[azzamasghar]

Hi Guys!!!

Thought i would pitch in here and give my experience on this issue. I've had a similar problem where in winter my car would be horrendous it would never warm up properly and id be sit there shivering like a jackhammer.

I changed the thermostat and it helped slightly but nothing to amazing. I then recently borrowed a VCDS cable from my friend and done a scan, it turns out there is an auxiliary heating, water pump inbetween the radiator and engine on the bottom side (belly pan/skid pan) I replaced this water pump and behold my temperatures were perfect, car warmed up a lot quicker and holds temperature now also!

Im entirely sure how this water pump helps keep the car warm or what has happened, but i have seen a significant increase in the car getting up to nominal temperatures quicker.

Hopefully this info will give you guys something to else to look into, and hopefully this will help you out! my car is a VW golf 2.0TDI 5 speed manual gearbox with the CBDC engine in case you have something similar


https://www.eurocarparts.com/ecp/c/Volkswagen_Golf_2.0_2010/p/car-parts/cooling/car-cooling-parts-and-car-heating/water-pump-gasket/?201440475&1&1fc9421388c1e13b05a850c308c7ee9a408f4c84&000366
This is the water pump i replaced.

 

[Tezzab]

Hi guys
Thanks to all who have posted as without you I would never have solved my coolant problem.
As with others my car over a period of 6 months was failing to reach full operating temp in colder weather and if it did as soon as I would begin to coast the temp would begin to fall. I will add that as with others the car would take quite a long time to reach the correct temp even from new. My vehicle is a skoda octavia 2litre diesel dsg, same as vw. Now as with others I replaced the main thermostat at great cost and no result.
I have had the same experience in Aus as well, nobody knows about this part at vw so I ordered the part to be told there are only 2 in Australia. I guess that if the dealers don’t know about the part there is no demand.
Now here is the very strange part of my experience. I replaced the part and it works perfectly, after 3km at 10 degrees the car is at full operating temp. The strange bit is that on inspection of the old part there was no thermostat inside. Same part number exactly. So I looked more closely and removed the clip that holds the two ends together. No sign of a thermostat in the plastic enclosure. Very very strange but the problem has been fixed.
Would be interested if anyone else has come across this.

 

[kinza]

Hi Guys
Interesting this Tezzab that you should say that its not a thermostat as such! I too have been having the same problems with my passat TDI DSG, which led me to this great forum, anyhow i took the airbox off to get a good look at the so called stat and to see if i could see the part number on it anywhere, couldnt see any numbers but it looks like the part 1ko121113a , so i ordered the part and plan to fit it when i get some free time, however with me handling the stat looking for the part number i must have knocked it, disturbed it in some way because the car is working as normal, Back up to temperature!! strange i know, but at least i have the part ready for if/when it goes again.
Kinza.

 

[Tezzab]

It’s a common problem for thermostats to stick open and then release. As you said it’s probably just the movement of the stat that’s made it close. They generally go on to stay open. It’s generally caused by a build up of corrosion over time