Coolant Leak?

[jms066]

Pile on --

2019 GTI with 17K miles. I've always thought I could smell a whiff of coolant, even when this car was new -- I've driven enough VWs over 40 years to learn that they all have these idiosyncrasies, and I figured I would just keep an eye on it. Three days ago I find a puddle of coolant under the car. Made an appointment for the 24FX ECU recall, and told them about the problem.

They just called me to tell me the thermostat housing was leaking, and they were going to replace the whole business. 17,000 miles... Thanks to everyone on the forum here for making me sound smart when I dropped it off this morning!

My service department at the local dealer is fantastic -- I've never had a loopback visit for anything they have done, and they have been very communicative and supportive.

This garbage is really starting to test my brand loyalty though...

 

[aloha_from_bradley]

Pile on --

2019 GTI with 17K miles. I've always thought I could smell a whiff of coolant, even when this car was new -- I've driven enough VWs over 40 years to learn that they all have these idiosyncrasies, and I figured I would just keep an eye on it. Three days ago I find a puddle of coolant under the car. Made an appointment for the 24FX ECU recall, and told them about the problem.

They just called me to tell me the thermostat housing was leaking, and they were going to replace the whole business. 17,000 miles... Thanks to everyone on the forum here for making me sound smart when I dropped it off this morning!

My service department at the local dealer is fantastic -- I've never had a loopback visit for anything they have done, and they have been very communicative and supportive.

This garbage is really starting to test my brand loyalty though...

I'm glad that you were able to get some useful information from this thread.

I wouldn't worry too much, as the coolant issue seems to be one of the only major things that creep up on the MK7s. I've had some other warranty work done on my car, but none of it has been critical / major mechanical in nature. The other piece, VW is really taking the thermo housing issues pretty seriously. There are been 5 or 6 iterations of this part, and they seem to be replacing them without much hassle. I've even heard of some cases where they are replacing them outside of warranty if you aren't too far out.

Let us know if the smell goes away. I can still smell coolant after driving even though my thermo housing & water pump have been replaced, though I'm not actually loosing coolant from what I can tell. There is a vent on the coolant reservoir, and I've had multiple technicians tell me that it's possible for coolant to evaporate from the system. I'm not sure how much validity there is to that. Every other coolant system I've worked on has been a sealed system.

 

[Vesta Turan]

Daughter's '15 GTI had an almost catastrophic loss of coolant on her way into work the other morning, had to have the car towed home. Pretty sure we have a cracked housing. We ran the car for about an hour yesterday in the garage and couldn't get it to leak, used the bore-scope today and found this:

My question is: could this NOT be the root of our problem? Certainly looks cracked, but is there any way that these cracks are not the source of the failure? We cleaned some of the coolant residue off of what we could reach the other day, cannot say for sure that the somewhat clean appearance of the area is due to that or not. I dont think we would have noticed the cracks had we not though, a few areas were just completely coated in coolant. Thanks in advance for any help!

 

[jimlloyd40]

Daughter's '15 GTI had an almost catastrophic loss of coolant on her way into work the other morning, had to have the car towed home. Pretty sure we have a cracked housing. We ran the car for about an hour yesterday in the garage and couldn't get it to leak, used the bore-scope today and found this:

View attachment 217030View attachment 217031View attachment 217032


My question is: could this NOT be the root of our problem? Certainly looks cracked, but is there any way that these cracks are not the source of the failure? We cleaned some of the coolant residue off of what we could reach the other day, cannot say for sure that the somewhat clean appearance of the area is due to that or not. I dont think we would have noticed the cracks had we not though, a few areas were just completely coated in coolant. Thanks in advance for any help!

It's hard to believe a crack would cause a catastrophic loss of coolant.

 

[battle.munky]

It's hard to believe a crack would cause a catastrophic loss of coolant.

The red exclamation triangle of doom and malcontent came on and everything. If it wasn't catastrophic, it was a few minutes away from it. Clearly, there's no way of knowing because it didn't get to catastrophe but we are assuming it was imminent. We could have easily assumed one could continue to run the car fine in that state as well I guess.

It isn't just sweating out like we've heard from other folks. It is odd though how we can't pay it to leak in the garage out of the same effin cracks in the housing.

 

[Vesta Turan]

It's hard to believe a crack would cause a catastrophic loss of coolant.

Are you saying that we might have an issue other than the cracks? She was close to sucking air when we got to her, I know that pressure can force a lot of fluid in a given amount of time, she drove with the warning light on for about 15 mins at 70 mph (I know... we've talked.) does that factor into a revised opinion on if the cracks could have produced the amount of coolant loss that she experienced?

 

[jimlloyd40]

Are you saying that we might have an issue other than the cracks? She was close to sucking air when we got to her, I know that pressure can force a lot of fluid in a given amount of time, she drove with the warning light on for about 15 mins at 70 mph (I know... we've talked.) does that factor into a revised opinion on if the cracks could have produced the amount of coolant loss that she experienced?

It definitely could be a crack but a crack wouldn't result in a catastrophic loss of coolant as you originally said.
It could be the crack but it took some driving to lose enough coolant to get the warning. Driving with the warning light on for 15 minutes definitely would make me change my opinion.

 

[Mikejt1954]

Hello Everyone,

2019 Golf R - 16k Miles

I've been smelling coolant after each drive for about a month now. Noticed I was loosing coolant, but topped it off and it's not moved much since. Went from the full line to the "min" line before I topped it off. I can also see dried coolant on the underbelly pan and collection points on the hoses under the tray.

Took the car to the dealership. They claim that it passed a pressure test and told me there was nothing wrong. Brought the car home and have been smelling coolant after each drive since then. The level hasn't moved much, but I can see that it's slowly making it way under the full line.

I know water pump / housing tend to leak on the 7/7.5 platform. I'm taking the car back to the dealership on Tuesday to complain again. Anyone else had this happen?

Trust me, the service manager knows all about the leak. It’s what happens when you use a composite water pump housing. There is a class action lawsuit already filed. Save all you receipts. Make sure the receipt mentions the problem. VW is desperate to crawl out from under this. And let’s not kid ourselves. They are NOT a “new” company, electric or not. And yes, mine does it too.

 

[aloha_from_bradley]

Trust me, the service manager knows all about the leak. It’s what happens when you use a composite water pump housing. There is a class action lawsuit already filed. Save all you receipts. Make sure the receipt mentions the problem. VW is desperate to crawl out from under this. And let’s not kid ourselves. They are NOT a “new” company, electric or not. And yes, mine does it too.

You must not have read through this thread.

My water pump & thermo housing were replaced months ago. I still smell coolant, and the tank still slowly drains. Albeit, much slower than before. It's gone from the top line of the reservoir to in-between the two lines since my last oil change. That was ~3k miles ago. So still a slow leak somewhere.

After more research, it seems that sometimes the hose fittings leak where they connect to the engine block, though I haven't been able to find anything to back up that idea.

As far as the class action suit, I think it's a waste of time. VW is trying to fix the issue. There have been somewhere around five different iterations of these parts. Even if you were outside of warranty, a call to VWA would probably fix your issue. An extended warranty on the parts would likely be the best outcome, especially if you are just outside of the warranty window. I wouldn't expect a whole lot in terms of hard cash.

 

[Al_in_Philly]

An interesting take on the use of plastic thermostat housings instead of aluminum, like they used to use:

 

[Sportbikemike]

I apparently have the same issue as others so I know it's not in my head. I smell the cooking of my coolant usually after about 10 minutes of driving. I lift the hood and can smell the warm engine but can't seem to see anything.
I took it in for an oil change 600 miles ago and they said I was low and had to add 2 quarts of coolant. And they pressure tested and said it came back normal.
My question is should I attempt to ask for a warranty replacement? I bought I certified used from VW and I have a warranty that is almost up.
Now I have a stage 2 so I don't want them to say it's my fault. I'd rather just get a better quality replacement and have my shop do it.
What would you guys recommend as a better than stiock replacement? I see multiple aftermarket options but I don't really see any posts on who runs what.

 

[jimlloyd40]

I apparently have the same issue as others so I know it's not in my head. I smell the cooking of my coolant usually after about 10 minutes of driving. I lift the hood and can smell the warm engine but can't seem to see anything.
I took it in for an oil change 600 miles ago and they said I was low and had to add 2 quarts of coolant. And they pressure tested and said it came back normal.
My question is should I attempt to ask for a warranty replacement? I bought I certified used from VW and I have a warranty that is almost up.
Now I have a stage 2 so I don't want them to say it's my fault. I'd rather just get a better quality replacement and have my shop do it.
What would you guys recommend as a better than stiock replacement? I see multiple aftermarket options but I don't really see any posts on who runs what.

If you were 2 quarts low you should have had a warning low coolant message in the MFD. Tell your dealer to manually inspect the thermostat housing for leaking. A thermostat housing leak will pass a pressure test because it only leaks when the engine is hot and running. My dealer warranted mine when I was tuned. I'm not aware of an aftermarket replacement.

 

[battle.munky]

Yeah, we just went through this last week with my daughter's '15 Mk7, there is no aftermarket replacement we found in the week's research leading up to it.

 

[BigSeaGJ]

The airlock is a really common and known issue, air not expelled from system at the factory leaches out over time causing coolant level to drop so it can appear to be a leak but in this case it’s not. Top up and is usually fine. I had to top mine up after several thousand miles, but all good since. I’ve had to top up coolant on every golf. Unless it is an actual leak, whereby usually some evidence to be seen or smelt. Water pump is a common failure.

 

[theDoktor]

Trust me, the service manager knows all about the leak. It’s what happens when you use a composite water pump housing. There is a class action lawsuit already filed. Save all you receipts. Make sure the receipt mentions the problem. VW is desperate to crawl out from under this. And let’s not kid ourselves. They are NOT a “new” company, electric or not. And yes, mine does it too.

Do you happen to have any information on how to get included in the class action lawsuit?
I documented a probable cooling leak that the dealer "couldn't find" while my car was still under warranty. They pressure-tested it, couldn't find anything (naturally), didn't look for leak evidence; just topped it up from the Min level it was currently at and sent me on my way. Coolant level continued to slowly drop (I have photos- time-stamped and dated) after this dealer visit, and the pink pool of water under the front of my GTI that happened whenever it rained, continued on. Finally the t-stat housing & water pump shit the bed big time two weeks ago; I was alerted when the low coolant sensor was triggered and the dashboard lit up. Dealer then lightened my wallet by $1100 and put in a new t-stat/water pump assembly. Next day on a 120 mile freeway cruise at 14 degrees F, I noticed the oil temp was running a bit higher than normal for those conditions- 220 degrees, and that my instantaneous and static fuel mileage numbers were noticeably lower than on previous trips under similar conditions. A week later under nearly identical temperatures, I observed that the car was REALLY slow to warm up, evidenced by both with temperature of heater output and the temp gauge, and that the oil temp was very sluggish to rise to operating temperature- like it took approximately 15 miles of freeway driving at 65 or so before everything got to normal operating temps. Naturally this morning's appointment at the dealer's service department found no issues & they couldn't duplicate the problem. I suspect, based on many decades of mechanical experience, that the new thermostat is sticking partially open; having experienced this issue in other vehicles, it probably won't get any better. Dealer isn't aware that I keep a detailed written log of everything that happens to the car, good and bad in addition to the service tickets.
Anybody got any (good) suggestions on how to proceed from here?