Glad you stuck to your guns. I had all those symptoms and was given the same brush off by many repair garages, despite sending them this forum. All seemed adamant it was the water pump or head gasket! I had some really sound information from @ shocks (thank you) on this forum about managing the situation on my return from Europe in the car, until I could get the heater matrix replaced. I did 4 months ago and I haven’t had an issue since! I will add that my blowouts were more frequent and prevalent during the warmer weather, but still, I’ve had nothing at all since the matrix was replaced! Local garage replaced for £380.
Coolant blown out from expansion bottle
- Thread starter andreykutyaev
- Start date
gertiethegolf
Member
Hi all!
I am legit freaking out over this thread. I have a 2014 VW Golf 110TDI 102,000km which suddenly started experiencing exactly the same issues described here..
Coolant bursting out the overflow, no overheating, only doing it every couple of weeks, only after freeway driving, passing pressure tests, slight exhaust fumes, none of the normal head gasket symptoms (everyone kept suspecting the HG but my gut said it wasn't) - the works. We did the waterpump change, replaced bottle replaced cap with no luck. This has been going on for about 3 months, 3 mechanics have looked at it and left scratching their heads. I was on the verge of cutting my losses and selling her but I love this car so much and was shattered at the idea of having to let her go. Then I stumbled upon this... Before I call my mechanic with the update - is there anything else I can do to further prove my suspicions of the Heater Matrix?
I am legit freaking out over this thread. I have a 2014 VW Golf 110TDI 102,000km which suddenly started experiencing exactly the same issues described here..
Coolant bursting out the overflow, no overheating, only doing it every couple of weeks, only after freeway driving, passing pressure tests, slight exhaust fumes, none of the normal head gasket symptoms (everyone kept suspecting the HG but my gut said it wasn't) - the works. We did the waterpump change, replaced bottle replaced cap with no luck. This has been going on for about 3 months, 3 mechanics have looked at it and left scratching their heads. I was on the verge of cutting my losses and selling her but I love this car so much and was shattered at the idea of having to let her go. Then I stumbled upon this... Before I call my mechanic with the update - is there anything else I can do to further prove my suspicions of the Heater Matrix?
anniebanani
New member
Hi @gertiethegolf, Do you have any update? Mine is EXACTLY the same story! I can't believe how much the same it is...
Started losing coolant fairly regularly around 6 months ago, mainly after freeway driving. Got progressively worse. Have had the EGR cooler replaced - still losing coolant, new waterpump - still losing coolant. This last episode saw the car in the workshop for 58 days - thank god they gave me a loan car FOC! Replaced the throttle body cooler something? (located at the front of the engine). They tested it before returning it - boom! still losing coolant. They removed the new, refitted the original and charged me for labour only. They've pressure tested it and it's fine. They've been in touch with VW. There's no sign it's the HG (no usual symptoms). Now they've pretty much given up on it I think. I get the feeling they never want to see it again......... BUT interestingly, they had it so long that by the time I picked it up the weather was cooler and I noticed that I have gurgling behind the dash and almost no heater. Apparently there's a RH flap fault in the AC which they say is what's causing the lack of heat. I'm no mechanic but I can't help thinking the issues are related so after hours of searching I've come up with this tread and I'm freaking out too!
We posed the heater matrix question to the workshop who said the lack of heat is likely the heater flap fault and they're reluctant to keep trying different things. They've suggested I take it to a VW dealer, which I'm reluctant to do.
It also sounds like @gertiethegolf and I own the same car! So if you've had an update, or if anyone else is experiencing the same, I'd love to know. I'm determined not to give up on this - I'm also determined not to mess with the HG etc. unless we absolutely know it's that and so far no one is convinced it is!
Started losing coolant fairly regularly around 6 months ago, mainly after freeway driving. Got progressively worse. Have had the EGR cooler replaced - still losing coolant, new waterpump - still losing coolant. This last episode saw the car in the workshop for 58 days - thank god they gave me a loan car FOC! Replaced the throttle body cooler something? (located at the front of the engine). They tested it before returning it - boom! still losing coolant. They removed the new, refitted the original and charged me for labour only. They've pressure tested it and it's fine. They've been in touch with VW. There's no sign it's the HG (no usual symptoms). Now they've pretty much given up on it I think. I get the feeling they never want to see it again......... BUT interestingly, they had it so long that by the time I picked it up the weather was cooler and I noticed that I have gurgling behind the dash and almost no heater. Apparently there's a RH flap fault in the AC which they say is what's causing the lack of heat. I'm no mechanic but I can't help thinking the issues are related so after hours of searching I've come up with this tread and I'm freaking out too!
We posed the heater matrix question to the workshop who said the lack of heat is likely the heater flap fault and they're reluctant to keep trying different things. They've suggested I take it to a VW dealer, which I'm reluctant to do.
It also sounds like @gertiethegolf and I own the same car! So if you've had an update, or if anyone else is experiencing the same, I'd love to know. I'm determined not to give up on this - I'm also determined not to mess with the HG etc. unless we absolutely know it's that and so far no one is convinced it is!
gertiethegolf
Member
@anniebanani hi! So I showed this thread to my mechanic who was mind blown haha. A week ago today I got him to bypass the heater core so we can see if the pattern changes. We noticed bubbling noises when we got home from picking it up and it lost some coolant (went below min) but this time it wasn't sprayed everywhere and it didn't completely drain out. Topped it up again and it dropped again after another freeway drive but once again, it only dropped to just ABOVE the min and held it there. We've topped it up again and it was fine over the weekend but only done local driving which it never plays up on local drives. We've got 3 more big freeway drives this week so I will report back in a week and let you know how I go... I don't think I'm out of the woods yet! Crazy how common of an issue it is with VWs yet no mechanic nor VW are aware to know how to fix it straight off.
anniebanani
New member
How'd you go? Is it still losing coolant? The weather here is cold and I've been doing mainly city driving so I'm only topping up coolant about once a week. Still no performance/engine issues but freezing my assets off as I have little to no heat so either way I'm going to have to have the heater fault fixed.....
gertiethegolf
Member
@anniebanani good news! 3 weeks today since heater core was bypassed and it has held the coolant in the exact same spot ever since. About 1500+km driving, freeway and local with absolutely no issues. It's been torture with no heat though - we're going through a bad bad cold snap here in Melbourne lol. Going in for fix on the 7th wooo!
gertiethegolf
Member
Update: had hc replaced and mechanic said there was a noticeable difference between the two heater cores when he blew into them - the old one had much more resistance. Nearly 2 weeks post replacement and no blow outs, however I have notices little drops of coolant in the driveway, no heat coming from foot vents, and irregular heat temps from the top vents (will blow warm air then go cold then piping hot). Latest thing I've notes is the sound of I assume coolant flowing behind the dash/vents. So back she goes on Thursday 
Not sure what the problem is now but it feels like something isn't wired properly.
Not sure what the problem is now but it feels like something isn't wired properly.
nathanso
Veteran Member
Your cooling system may have air trapped in it. Purging air from these systems is notoriously difficult as documented elsewhere on this site.
gertiethegolf
Member
It would explain the water flow noise, but I don't think it explains the drops of coolant in the driveway, non existent foot heat or the random temperatures coming from the vents would it?
nathanso
Veteran Member
If the level in your coolant expansion tank is indeed dropping it would indicate a second issue, a leak, most likely resulting from the recent work. Lots of air in the heater core portion of the cooling system could produce sporadic cabin heating, I would think.
Golf mk7 2014 80 k miles same symptoms as above.
Engine mount replaced by local garage and coolant reservoir obvs pulled over and probably shook up a bit. Garage said they did not drop coolant. Suspect bag has ruptured or more sand in matrix. I am getting the DPF regen blowout like others.
Valeo matrix is £70 on AUTODOC. Vacuum kit is £30 on eBay. Coolant/flush etc probably £40. New tank is £30.
Contacted some local VW specialists. One knew exactly what it was … £500 ish using genuine parts. Another garage £1200! Because they said flushing will take a long time.
I will do this myself as I want to do a good write up! This should be a recall …
Engine mount replaced by local garage and coolant reservoir obvs pulled over and probably shook up a bit. Garage said they did not drop coolant. Suspect bag has ruptured or more sand in matrix. I am getting the DPF regen blowout like others.
Valeo matrix is £70 on AUTODOC. Vacuum kit is £30 on eBay. Coolant/flush etc probably £40. New tank is £30.
Contacted some local VW specialists. One knew exactly what it was … £500 ish using genuine parts. Another garage £1200! Because they said flushing will take a long time.
I will do this myself as I want to do a good write up! This should be a recall …
Can anyone recommend a replacement part heater Matrix that is none VW with wider channels and where in the uk they can be obtained. Also when replacing do you require new seals and brackets to hold the pipes on And can you just clamp the water hoses under the glove box area. Mine is a 2013 Golf TDI Gt model
pretty sure this is the company that manufacture wider holes.
Car Heater Matrixes - The Car Heater Shop
we provide and manufacture quality car heater matrixes for domestic, commercial, plant and agricultural vehicles.
www.motoradsonline.co.uk
Although, I’m of the opinion … if the matrix isn’t blocking the crud … then it’s getting blocked elsewhere! I got genuine one off eBay for 70
I replaced my matrix and it was unbelievable the crud that came out of it. After multiple hours of research,I genuinely think the bags don’t split… on the contrary, people remove the bags which the coolant depends on… which then creates drop out in the liquid. it is the removal of the bag without putting new G12 Evo coolant in it which causes issues (I believe). The bags are so tough, they normally split when people try and get them out with tweezers? I do also think casting sand has something to play in this though.
Btw if anyone wants the G12 Evo coolant, I’ve got 5L genuine VW tub still sealed in the garage, which I’m happy to post for 20 + postage.
cheers
Thanks for that the car has had a new waterpump a few weeks ago a new cap pressure tested and runs fine it’s all now pointing to the matrix as once flushed it was refilled with the correct G12 I can do the matrix but wondered if the system needs bled after or if I clamp the pipes will it be ok. There seems to be a running theme with Golfs Skoda and Leon’s with the matrix getting blocked and I agree it could be poor coolant to or none change of coolant surely W have now addressed this faulton the 2l TDIpretty sure this is the company that manufacture wider holes.
Car Heater Matrixes - The Car Heater Shop
we provide and manufacture quality car heater matrixes for domestic, commercial, plant and agricultural vehicles.
Although, I’m of the opinion … if the matrix isn’t blocking the crud … then it’s getting blocked elsewhere! I got genuine one off eBay for 70
I replaced my matrix and it was unbelievable the crud that came out of it. After multiple hours of research,I genuinely think the bags don’t split… on the contrary, people remove the bags which the coolant depends on… which then creates drop out in the liquid. it is the removal of the bag without putting new G12 Evo coolant in it which causes issues (I believe). The bags are so tough, they normally split when people try and get them out with tweezers? I do also think casting sand has something to play in this though.
Btw if anyone wants the G12 Evo coolant, I’ve got 5L genuine VW tub still sealed in the garage, which I’m happy to post for 20 + postage.
cheers
By the way did it remedy the problem
Yes, it works perfect. Similarly, mine played up after they changed my water pump / timing belt.
Look for the tell tale signs of pink / white spots over the engine mount. you’ll also notice your coolant level drop and might even hear it bubbling whilst driving.
You need to buy a Vac kit (ebay £30) to do the job. They don’t have bleed screws. It is a must otherwise, you’ll probably end up with air in the system (and it’s actually quicker to do it via vacuum)
For £30, I also swapped out new coolant expansion tank.
Can I ask where you bought the matrix I just want to get the correct one with new clips. How does the vacuum work this is the first time I have heard of this as most squeeze the pipes then top up and leave the coolant cap off while it heats up. I think it’s poor design by VW and they must know I imagine the new golfs have a different matrix by now.
FJBGTD
Member
There are 2 types of matrix fitted, you need to pull off the trim in the footwell to check which you have. The Valeo unit has "Valeo" stamped on the plastic housing, the other unit I believe is Denso. The Denso unit is very different and has pipe tails coming out of the matrix, where as the Valeo unit has the connections directly onto the matrix. You must order the correct unit, they are not interchangeable.
The MK7.5 Golf has an updated matrix and is compatible with the MK7, if you buy a Nissens unit it will be the updated version. You can get the part number from the Nissens online catalogue. Nissens units are OEM quality and come with replacement clips an orings.
The MK7.5 Golf has an updated matrix and is compatible with the MK7, if you buy a Nissens unit it will be the updated version. You can get the part number from the Nissens online catalogue. Nissens units are OEM quality and come with replacement clips an orings.
Thanks very much for this informative reply I will start stripping the glove box etc shortly so will get the details of the heater then and will take photos as I go.Does the system need vacuum filled after or does a slow fill up with pushing the hoses stopping and filling get the air out to.I have read the sat nav unit may need to come out to for which removal keys are needed. The main problem people seem to encounter is getting the pipes off and the top clip which has a tab that needs pushed back
FJBGTD
Member
You will not need to vac the system if you are only changing the matrix providing that you only drain the matrix. You can do this by disconnecting the 2 quick connects on the bulkhead behind the engine. You are meant to use a scan tool to bleed the system as you need to activate the 2 electric pumps. With VDCS first bleed the cooling circuit in Adaptation: Bleed cooling circuit, follow the instructions on screen, then in Basic Settings: Bleeding of low temperature circuit, add 4 seconds in the box. OBDeleven can be used to bleed the main cooing circuit, but does not work on the low temperature circuit, at least not the last time I tried (it may have been updated since).
I thought I could have got away with disconnecting the matrix pipes plugging each as it comes off then replacing the matrix and filling it in position with a syringe then reconnect the pipes. I have seen a few done then the engine started with cap off then stop check pipes squeeze and top up and continue I have a scan tool basic code reader clearer never done this with it.just don’t want to do any damage all videos just show the matrix pulled out with coolant collected then once reconnected filed gradually and as said pipes squeezed and rechecked it’s a 2013 2litre TDI and thanks for the reply.
When you did this job was there any special way you refilled the system after eg bleed it thanksTo reply to Theo95, you've mentioned something that I neglected to mention in my previous posts regarding my experiences. Because I had the issue for so long, I also noticed that if a regen was carried out when the car was stationary then no overflow occurred.
As DrSchultze suggested, all your symptoms seems to match those of other members so I'd start by changing the heater matrix. Attached are some photos of my own when I swapped them out. Part number 5Q0.819.031.
FJBGTD
Member
That may work, but I have not tried it without VCDS.
To reply to Theo95, you've mentioned something that I neglected to mention in my previous posts regarding my experiences. Because I had the issue for so long, I also noticed that if a regen was carried out when the car was stationary then no overflow occurred.
As DrSchultze suggested, all your symptoms seems to match those of other members so I'd start by changing the heater matrix. Attached are some photos of my own when I swapped them out. Part number 5Q0.819.031.
wondered could you just do it with a vaccum the refill and after never seems to get much mention in any vids. When you bled were the pipes rejoined in the bulkhead
FJBGTD
Member
Yes everything reconnected and I bled using the proper procedure using VCDS. The problem is that there are 3 pumps, 2 electric and 1 electro mechanical, and you need a scan tool to activate them. I don't know if it works without it, as I have had VCDS for years since my MK5 days.
These 2 videos are worth a watch
SkilledMilk
Member
I covered the footwell with towels and plastic sheets to catch any spillage, which was relatively minor and seemed to be only the contents of the connecting pipes that spilled out. I didn‘t do any special bleed or flush after, given the minimal loss of coolant. Kept an eye on the level in the expansion tank over the following days and topped up when needed.
It’s been fine since, with no drop in level over the 60k miles covered.