Coolant blown out from expansion bottle

AdrianC

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Joined
Jul 16, 2019
Location
Ireland
TDI
Golf VII GTD
This is frustrating indeed :)

:) :) Thanks for keeping this topic alive, i would be great if we can look back at this topic in some time.

To my opinion your heater matrix is not working as it supposed to do, i would replace the heater matrix. I found this document where is explained that you should flush the system properly. https://drive.google.com/file/d/0ByxgazxO4YLZV0hyTm1OVm1tNE0/view
In this document the EGR is mentioned. My engine is not mentioned in this document, aluminium rust, flux and the EGR do ring a bell......


NEXT :)
Thanks for posting this link.

I've re iterated this to my mechanic and assures me he will flush the system twice.
See how I get on this Thursday...

I am confident that this will solve the problem.

By the way, would anybody recommend a Valeo or Nissens Heater core?

I said to him to put which one he thinks is best..
 

BirdmanofTas

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Joined
Aug 13, 2019
Location
Australia
TDI
2013 Golf Mk7 Highline TDI
the one i have just received is a Nissens, and it is a revision B, this is the latest version, and i believe the passageways are larger.. but i have yet to remove the existing core, but when i do i will measure, and cut the old one apart to have a look at the internals.. will be this weekend.
 

SkilledMilk

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Joined
Mar 31, 2018
Location
Glasgow
TDI
Leon MK3 (184) 2013
the one i have just received is a Nissens, and it is a revision B, this is the latest version, and i believe the passageways are larger.. but i have yet to remove the existing core, but when i do i will measure, and cut the old one apart to have a look at the internals.. will be this weekend.
I thought the passages looked larger on the Nissens one also. The replacement ones that the dealerships are offering my be the same as the one they are replacing which may be a reason the problem is not fixed in those instances?

Be interesting if you could try to blow through each matrix when you're replacing it this weekend. In my case there was significant resistance in the old core versus the brand new one.
 

BirdmanofTas

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Aug 13, 2019
Location
Australia
TDI
2013 Golf Mk7 Highline TDI
I thought the passages looked larger on the Nissens one also. The replacement ones that the dealerships are offering my be the same as the one they are replacing which may be a reason the problem is not fixed in those instances?
Be interesting if you could try to blow through each matrix when you're replacing it this weekend. In my case there was significant resistance in the old core versus the brand new one.
I will do, i am also going to do a volume measurement to see if there is a significant difference before i cut it open.. will let you know the result.
 

BirdmanofTas

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Joined
Aug 13, 2019
Location
Australia
TDI
2013 Golf Mk7 Highline TDI
I thought the passages looked larger on the Nissens one also. The replacement ones that the dealerships are offering my be the same as the one they are replacing which may be a reason the problem is not fixed in those instances?
Be interesting if you could try to blow through each matrix when you're replacing it this weekend. In my case there was significant resistance in the old core versus the brand new one.

I couldnt wait, so took some time off work, and replaced the matrix.. volume of the new unit 165ml, volume of old 150ml. when blowing through the matrix, the new one had no resistance, the old one had resistance.. i filled the old matrix with water (both inlet and outlet) and when held vertical, it would not drain out all of the water, i had to turn it upside down.. (i videoed it, but doesnt really show well).. i cut the top and bottom off the old matrix, and i cannot see a light through it, when a torch is held up to it, and i look down the channels.. so it definitely was constricted.. i will do some test runs, confirm i have the coolant level right, and see how we go.. i will report back in a day or so.. cheers..
 

wonneber

Top Post Dawg
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Oct 12, 2011
Location
Monroe, NY, USA
TDI
2014 Jetta Sportwagen, 2014 Tiguan,2003 Jetta 261K Sold but not forgotten
Roughly how long did it take to change it??
Curious.

Back in the old days a radiator shop could take the top tank off the radiator and run a tiny rod through the cores to clean them.

Guess this doesn't happen any more. :eek:
Throw away parts.
 

BirdmanofTas

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Joined
Aug 13, 2019
Location
Australia
TDI
2013 Golf Mk7 Highline TDI
Roughly how long did it take to change it??
Curious.
Back in the old days a radiator shop could take the top tank off the radiator and run a tiny rod through the cores to clean them.
Guess this doesn't happen any more. :eek:
Throw away parts.
total to get it out, and replace was about 1.5hrs, mainly because i had trouble getting the top pipe clamped up again properly.. the Nissen kit came with a clamp (like the one on the bottom pipe) not the clip that VW use.. i gave up and put the clip back on.. in the Matrix (radiator) the cores are approx 1.5mm wide internally by about 20mm so would be difficult, and expensive to clean.. cheaper to buy new.. the Nissen kit cost me $160 AUD (about 80 euro) delivered from the US to Australia..
 

mm-rocco

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Jul 31, 2019
Location
Netherlands
TDI
MK7 GTD 2016
Today my heater matrix was replaced at the dealership. I just had a long motorway drive doing 130/140 km/h, after the DPF-regen finished and the exhausttemp was down tot 250C i pulled over and checked the coolant. No blowout this time !!!!


I will keep you informed !
 

BirdmanofTas

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Joined
Aug 13, 2019
Location
Australia
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2013 Golf Mk7 Highline TDI
Today my heater matrix was replaced at the dealership. I just had a long motorway drive doing 130/140 km/h, after the DPF-regen finished and the exhausttemp was down tot 250C i pulled over and checked the coolant. No blowout this time !!!!
I will keep you informed !
Good news...., I too took mine for a run, unfortunately 130/140 out of the question, legals 110 here. did a run without Regen that usually caused issue with or without Regen, and levels remained fine.. so far so good..

did another run this afternoon, that included a Regen, and the level of the coolant tank didnt change more than a couple of mm's so i confirm that the replacement of the Heater matrix, has fixed the issue on my car..

previously this run would cause coolant boil over and gurgling in the dash no matter what.. it is a run of 100 Kms mainly Highway, cruising on 115ish kmh ☺..
 
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Kamei1507

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Aug 29, 2019
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Holland
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Seat Leon st 1.6tdi 12/2014
Hello,

I was following this thread with big interest because i had/have the same problems. Ive changed the heater matrix also yesterday. but i have this problem or question before this heater problem started my oil temperature was 107/108 Celsius when driving 140km/h now in slowly goes to 120 Celsius and it takes forever to cool down i have an obd tool with torque on phone coolant rises till about 96,5 Celsius. My 1.6tdi 12/2014 has 139xxx km on it possible waterpump issues? I was on holiday to Italy when i noticed this full load three people in the car and driving 140 till 170km/h in Germany looked at oil temperature wow 120 Celcius maybe regen but it stayed there all the time outside temps 20 till 30 Celsius. Now when i drive alone it hits the mark of 120 Celsius also.

Sorry if i write it a bit out of order but trying to explain it (LOL)

Regards Karsten
 
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Adyzds

Member
Joined
Aug 29, 2019
Location
Romania
TDI
Golf 7 2.0 TDI
Jesus Christ, guys

I'm so happy I've found this topic. I asked on multiple forums in Romania but none had the answer.

I had the same problem and it was extremely frustrating since I'm dealing with this from last summer. My mechanics knowledge is very limited and it blows my mind you figure it out that DPF regen is the cause.

I thought the head gasket was the issue and the problem starts when I'm running over 110km/h. I'm so glad I didn't replaced the head gasket.

I thought the problem reproduces only on warm weather since from November to May I haven't lost 1ml. Of course in november I started using heat and maybe thats the reason
A weird thing (maybe unrelated to this problem) is that in the first minutes after running the engine, a burnt bad smell comes from the vents and the mechanic said that the radiator is clogged which is a common side effect of a malfunctioning head gasket.
He cleaned the installation from bacteria and then the car was not producing enough heat and the smell was still there. He disabled from VCDS the auxiliary heat (don't know how to translate this in English, lol) recommending me to change the radiator afterwards, which I don't.

I still don't know how it haven't blown coolant from March to beginning of August (when it started again). I have been on the highway and nothing happened.

Now it makes much more sense. Thank you so so much for posting your updates. Some guys in RO said that if its not the head gasket, it might be the EGR cooler... so I would have spent a lot of money for nothing.
 

DrSchultze

Member
Joined
Jul 15, 2019
Location
Denmark
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Audi A3 2.0 2013
Today my heater matrix was replaced at the dealership. I just had a long motorway drive doing 130/140 km/h, after the DPF-regen finished and the exhausttemp was down tot 250C i pulled over and checked the coolant. No blowout this time !!!!


I will keep you informed !
Actually the best way to test, would be to pull over during DPF regen, this will create the worst possible scenario, with limited airflow in the engine compartment, and reduced coolant flow because of low engine RPM, and the auxiliary pumps to do most of the coolant circulation.
 

mm-rocco

Well-known member
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Jul 31, 2019
Location
Netherlands
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MK7 GTD 2016
My car was in for problem-solving this week at the dealership, we agreed he would run Tpi 2040004/9 "Prüfplan zum Kühlmittelverlust beim EA288 Dieselmotor". After a few hours i received a phonecall from the dealership that the computer diagnosed the EGR and the head and not the heater matrix !!! I asked the dealership to replace heater matrix and leave the EGR and head for the moment.


If the heater matrix is really the faulty part causing the coolant blow out loads of people must have spent fortunes on parts and labour.


So far so good, first DPF-regen was fine. See what happens next week !
 

Gottfried

Member
Joined
Nov 4, 2018
Location
Slovenia
TDI
Golf Mk7 variant
I am wondering about one thing, looking into this matter i do not seem to find any other VAG cars with similar issue, or am I wrong? What does golf have that A3 or rapid or leon dont?
 

BirdmanofTas

Member
Joined
Aug 13, 2019
Location
Australia
TDI
2013 Golf Mk7 Highline TDI
My car was in for problem-solving this week at the dealership, we agreed he would run Tpi 2040004/9 "Prüfplan zum Kühlmittelverlust beim EA288 Dieselmotor". After a few hours i received a phonecall from the dealership that the computer diagnosed the EGR and the head and not the heater matrix !!! I asked the dealership to replace heater matrix and leave the EGR and head for the moment.


If the heater matrix is really the faulty part causing the coolant blow out loads of people must have spent fortunes on parts and labour.


So far so good, first DPF-regen was fine. See what happens next week !
Hi MM-Rocco, i agree people have spent a lot of money to not fix this issue..
The lady i bought my car off had replaced the coolant tank and cap, the EGR Cooler, the radiator, the water pump and had been quoted to replace the head gasket, even though there were no gasses in the coolant, which is why she sold it to me cheap.. the symptom are similar to the EGR Cooler leaking or head gasket though it would happen all the time, not only at highway speeds.
I replaced the engine complete in mine, because it was cheaper than doing a head gasket only to find the issue still there..
all the tests since replacing the heater matrix have been fine, i have not had an issue, so am now happily motoring without the worry. cheers.
 
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SkilledMilk

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Joined
Mar 31, 2018
Location
Glasgow
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Leon MK3 (184) 2013
I am wondering about one thing, looking into this matter i do not seem to find any other VAG cars with similar issue, or am I wrong? What does golf have that A3 or rapid or leon dont?
I have a Leon and had this issue. As the golf, A3, Leon etc are based on the MQB platform, it's a VAG issue not specific to the golf. The issue may appear to be more prevalent in golfs because there are more of them.
It's really interesting to me that many on this thread have now apparently sorted the overflow problem by changing the heater matrix, while VW dealers are still saying it could be the head gasket and egr cooler.
 

mm-rocco

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Jul 31, 2019
Location
Netherlands
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MK7 GTD 2016
Since the replacement of the heater matrix i drove 752 KM, I had three DPF-REGEN's and even pulled over in the middle of a DPF-REGEN. No blowout's and no loss of coolant !



How are you all doing ???
 

Gottfried

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Nov 4, 2018
Location
Slovenia
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Golf Mk7 variant
@SkilledMilk then I was mistaken, Good to know. How come then mechanics don't know more about it since it seems it is quite unusual issue. At least official dealers should know.
@mm-rocco god I hope you solved it. I keep fingers crossed as I often drove more than 800 between coolant losses but I am staying optimistic.

BTW another mechanic I spoke to was convincing me that heater matrix is not the issue and pointed towards EGR.
 

Adyzds

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Aug 29, 2019
Location
Romania
TDI
Golf 7 2.0 TDI
Since the replacement of the heater matrix i drove 752 KM, I had three DPF-REGEN's and even pulled over in the middle of a DPF-REGEN. No blowout's and no loss of coolant !



How are you all doing ???
Good to know. I'll do the procedure later this month and will come back with results. (2 years of struggle here)
 

AdrianC

Member
Joined
Jul 16, 2019
Location
Ireland
TDI
Golf VII GTD
Have just had my heater matrix replaced but nothing to report as yet as I've just been going on short journeys..
Ill have a decent run (200 mile round trip with motorway speed) this weekend and hopefully nothing will happen.

Will update later
 

mm-rocco

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Jul 31, 2019
Location
Netherlands
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MK7 GTD 2016
Have just had my heater matrix replaced but nothing to report as yet as I've just been going on short journeys..
Ill have a decent run (200 mile round trip with motorway speed) this weekend and hopefully nothing will happen.

Will update later

Do not panic when the coolant-level drops a bit, this seems to be normal. I had this the first day and started to feel sick again :) The car only needed 200ml. Today i put another 200km on, still good !
 

AdrianC

Member
Joined
Jul 16, 2019
Location
Ireland
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Golf VII GTD
Do not panic when the coolant-level drops a bit, this seems to be normal. I had this the first day and started to feel sick again :) The car only needed 200ml. Today i put another 200km on, still good !
I will take your advice :):)
Thanks
 

BirdmanofTas

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Joined
Aug 13, 2019
Location
Australia
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2013 Golf Mk7 Highline TDI
Do not panic when the coolant-level drops a bit, this seems to be normal. I had this the first day and started to feel sick again :) The car only needed 200ml. Today i put another 200km on, still good !
@mm-rocco i second this, as my coolant did drop a small amount on the second run i did, (about 100ml) but nothing since, done about 750K's now and have not had an issue since the matrix replacement..
 

Spipa

Active member
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Jul 18, 2019
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Netherlands
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Mk 7 GTD
Do not panic when the coolant-level drops a bit, this seems to be normal. I had this the first day and started to feel sick again :) The car only needed 200ml. Today i put another 200km on, still good !
I’m glad that the problem is now probably fixed for you man. Can you tell me how much you have paid to replace the heater matrix? And at which dealer? I don’t trust mine anymore..
 

mm-rocco

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Jul 31, 2019
Location
Netherlands
TDI
MK7 GTD 2016
Here a little update: i drove 1483 km since the replacement of the heater matrix, since then i had no blow outs of coolant and could not find any pink spots or pink marks of coolant nearby the reservoir. In the last 1483 km i topped up coolant twice, in total 400 ml. How are you guys doing ???
 

BirdmanofTas

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Aug 13, 2019
Location
Australia
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2013 Golf Mk7 Highline TDI
i have done approx 1000 Kms, and have only added 100ml of coolant after the second run, i am taking photos of the coolant tank every few days to monitor the level when hot and cold to see if it varies much.. it may have dropped about 3mm on the coolant line, but is still about half way up the markers for the min and max levels.. when dead cold.. so i think that it is about right.. will inform of changes if any.. cheers..:)
 

Theo95

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Sep 9, 2019
Location
Romania
TDI
Golf 7 2.0 TDI
Hello. I have a similar problem as you, my car looses coolant when the DPF finishes the regeneration. I'll tell you my story maybe we can solve this together.

I have a 2013 Golf Mk7 2.0 TDI DSG. I bought it 4 months ago with this problem. Unfortunately the DPF did not regenerate when I was checking the car. I bought it with 160k kms and now it has 166k. The water pump and timing belt were changed at ~145k. The previous owner says the car did not had any problem when I bought it from him, but I don't believe him because he took a bottle of antifreeze out of the trunk when he gave me the car. Other than that, on the coolant tank there is a G12 sign. As far as I know we should put G13 coolant in our Golfs so I'm not really sure if that was changed.

I went with the car at the VW Dealership. They said they did a pressure test and checked the car for 4 hours and the conclusion was that there's nothing wrong with the car. When I arrived at the Dealership the car just started regenerating the DPF so I'm pretty disappointed with them. I paid for nothing. They suggested me to change the coolant tank cap. I bought a new aftermarket cap and the behavior changed a little bit. With the old cap the coolant was overflowing near the cap itself. With the new cap the coolant overflows at the bottom of the tank. So we have nothing so far.

After this I went with the car at a different car service. Here the things start to become interesting. The VCDS was not showing any relevant errors and the fans were working fine. They started an active regeneration from the VCDS with the car staying still. Nothing happened. After this they took the car at a drive with the regeneration ongoing and drove it with 200 km/h and said still noting happened. The only thing that they found was the AC radiator that was half damaged and said it may overheat and is restricting the airflow to the water cooling radiator. They changed the AC radiator and for the first 2 or 3 regens it seemed that the problem got solved... but it didn't.

I noticed the amount of coolant that is overflowing is not constant. It ranges from a few drops to a full liter. But I also noticed there are some variables. It overflows more coolant when the AC is on, when the engine has higher RPM and in general when there is a higher load on the engine like when going uphill or when the car is full. But mostly the AC and the RPMs are taking a big part of this. I think this is pretty important. Usually driving in town with AC off with low RPMs or with 70 km/h in 6th gear nothing happens. This lead me to think that the head gasket is the problem, but it only happens when the DPF is regenerating and it doesn't make sense. Or maybe the cylinder head itself has a leak when it heats from the DPF.

I also noticed sometimes the right vents are not blowing hot air. I haven't tested this that much since is summer right now and I usually don't drive alone outside of the city. I heard that some of you have better results when setting the heat to high when the regeneration starts. The VCDS showed an error regarding a faulty flap. I deleted it and I don't know if it appeared again. I'll have to investigate this further.
One more thing that I want to mention is that I saw some debris in the coolant tank. I don't know if they are from eventual leaked gases or corrosion. Or maybe they are present because the tank could have been changed with a used one. The coolant itself looks crystal clear. I uploaded 2 photos.

https://imgur.com/ZXTUYyS
https://imgur.com/NXuC3Sm

I'll have to make some long roads in 2 months so I'm thinking as a temporary fix to buy a bluetooth car tester and make it notify me in a way or another when the regen starts so I can slow down and turn the AC off. Do you have any ideas for this? I hope this is not the case and I'll fix the issue by then.

I saw that some of you have changed the heater core. I'm looking forward to more feedback from you. I saw there are two types of Nissen heater cores: one for Denso heaters and another for Valeo heaters. What part number did your new heater cores have?

Come on guys, let's figure this out because it is really frustrating.
 
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DrSchultze

Member
Joined
Jul 15, 2019
Location
Denmark
TDI
Audi A3 2.0 2013
If your heating is failing, and you have overflow of coolant, I'd start by swapping the heater matrix, it's a 2 hour job. If this doesn't fix the problem, you can start searching for other problems, but at least you will have a toasty car when winter is coming. ;)

As for the prevoius owner, he probably visited a random workshop, that swapped the water pump and expansion tank, and when this didn't fix the issue, he got a quote on a new head gasket, and decided to sell the car.

I don't have the P/N for the matrix nearby.
 
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