Failed Thermostat Housing/Coolant Loss Info Gathering

[RichardCranium]

Just got my 40K mile, 2017 Sport back from the dealer to check for a leak. Naturally the system held pressure- I was told by the Service Writer that the coolant "just evaporated" from the system. And can anyone explain to me just how evaporation occurs in a sealed, pressurized cooling system? Who wants to be the first to volunteer to use just their hands to remove the overflow tank cap for me the next time the car gets warmed-up? Those warning stickers on the cap are just B.S., right?
So the dealership "topped off" (in writing, too!) the overflow bottle by overfilling it to the seam, not the Max line. It took less than 10k miles for the level to drop below the Min line prior to the coolant loss to start happening. I wonder how long it will take this time? At least I now have dated photos to document the various coolant levels. Looks like I need to get it up on a lift, take the splash pan off & take some photos from below as recommended by a previous poster. (Thanks for the heads-up!)

I had an identical experience with my car.

"Hurr durr, it holds pressure so there's nothing wrong!"

Yeah, ok. It's a supposedly sealed system so that antifreeze is going somewhere, and I shouldn't be having to add coolant every few months on a relatively newer car.

I'm contemplating getting rid of it before it gets truly up there in age. Does anyone know if the R has the same problem?

 

[ReadTheBook]

Lol, yes, they do. Google the Ford Powershift transmission debacle. Instead of redesigning the transmission, they chose to continue on with the problematic design, and it's cost them billions in warranty repairs. They knew even before the transmission made it into production that it was a piece of trash and they ignored it.

https://www.caranddriver.com/news/a27438193/ford-powershift-transmission-problems/

My co-worker had 4 transmissions in his Fiesta. Ford did not give a FUCK.
Most Subaru CVTs transmissions also fail in cars that are of the generation currently around 10 years old, not sure if that's still the case.

 

[RichardCranium]

My co-worker had 4 transmissions in his Fiesta. Ford did not give a FUCK.
Most Subaru CVTs transmissions also fail in cars that are of the generation currently around 10 years old, not sure if that's still the case.

Yeah, my last car was a Focus with the effected transmission. It was a piece of garbage. It would take a lot to get me back into another Ford. I can deal with the car breaking, because cars break, but it's principle behind Ford not giving a shit less about the problem and generally ignoring it that turned me off of FoMoCo after having purchased three brand new Fords over the past few years. They made it very clear that profits are more important than taking care of their customers.

Subaru CVTs aren’t great either. I know when the 2015 WRX came out, guys were trying to track their CVTs, and they’d overheat after a couple of laps and go into limp home mode. I really like Subarus, and considered a WRX before I bought my GTI, but I needed some version of an auto, and the VW DSG is just a far superior transmission.

 

[jimlloyd40]

I had an identical experience with my car.

"Hurr durr, it holds pressure so there's nothing wrong!"

Yeah, ok. It's a supposedly sealed system so that antifreeze is going somewhere, and I shouldn't be having to add coolant every few months on a relatively newer car.

I'm contemplating getting rid of it before it gets truly up there in age. Does anyone know if the R has the same problem?

Not only does the R suffer from the problem all the Golfs do including the TSI.

 

[surfstar]

Well, the phone call to VW "care" didn't work. I forwarded them the invoice via email after the initial phone call for further review.
After a few days, they called back and said - nope, not covered under powertrain warranty.

So, I have written a letter, included the Reddit thread with highlighted posts of each person that confirmed they were covered under powertrain warranty and sent it via certified mail, hard copy. Not email. Usually old-school can help, along with threats of social media (new school) might prove helpful... we shall see.

UPDATE

Certified letter was received by VW in first week of Dec. Never heard a word. No email, no letter, no phone call.
Didn't do anything over the holidays - assumed we'd hear from VW eventually.
Nope.
Finally followed up last week with an email to VW customer care, attaching a scanned copy of the letter (with the Reddit thread attachment), asked them to have a supervisor or manager review the letter and finally provide a response, as none had been received.
Got a phone call a few days later, saying that VW will be sending a check to reimburse the full amount - that the repair should have been covered under warranty.

THANKS TO THE OP FOR STARTING THIS THREAD! Assuming we get the check (should arrive in a few days - update: it was received. Happy ending.), you were helpful in getting $1200 back for my mom. Much appreciated.
Fingers crossed this doesn't happen on my 2016 GSW (just about 62k miles now, no issues... yet) - I'd probably take to an indy for repair out of pocket.

 

[ReadTheBook]

UPDATE

Certified letter was received by VW in first week of Dec. Never heard a word. No email, no letter, no phone call.
Didn't do anything over the holidays - assumed we'd hear from VW eventually.
Nope.
Finally followed up last week with an email to VW customer care, attaching a scanned copy of the letter (with the Reddit thread attachment), asked them to have a supervisor or manager review the letter and finally provide a response, as none had been received.
Got a phone call a few days later, saying that VW will be sending a check to reimburse the full amount - that the repair should have been covered under warranty.

THANKS TO THE OP FOR STARTING THIS THREAD! Assuming we get the check (should arrive in a few days), you were helpful in getting $1200 back for my mom. Much appreciated.
Fingers crossed this doesn't happen on my 2016 GSW (just about 62k miles now, no issues... yet) - I'd probably take to an indy for repair out of pocket.

I am thrilled to hear that you were able to work this out. Though it was not without hassle, I think this is a good example of how these threads can help out.

 

[theDoktor]

I checked my coolant level this morning- 2 days and approx. 201 miles after the dealer topped-off the coolant tank. Both times the engine was stone cold and had not been started yet. First photo was at the dealership when I picked-up the car. Second was in my driveway this morning. Note the difference in coolant levels in the tank.
Looks like I'm about to have another conversation with the dealership Monday morning...This will be followed by a conversation with the VW Zone Rep if the dealership doesn't take action.

 

[mopar22]

I checked my coolant level this morning- 2 days and approx. 201 miles after the dealer topped-off the coolant tank. Both times the engine was stone cold and had not been started yet. First photo was at the dealership when I picked-up the car. Second was in my driveway this morning. Note the difference in coolant levels in the tank.
Looks like I'm about to have another conversation with the dealership Monday morning...This will be followed by a conversation with the VW Zone Rep if the dealership doesn't take action.

It takes a few runs to settle tbh. If they didn't bleed teh system (just like from the factory) there will be a bubble in the system they will self bleed out.

 

[theDoktor]

I would agree if any of the system components had been removed or replaced. That will definitely introduce air into the cooling system, creating air bubbles that need to be bled out. With the overflow tank at the high point of the system, removing the cap and adding coolant actually reduces the inherent volume of air in the cooling system. Air, being lighter than liquid, migrates to the high point of the system (the overflow tank.). This limited volume of air is always in the system and provides the necessary expansion space when the system is heated and pressurized. (Boyles Law???) Not necessary to bleed the system when adding coolant.

 

[mopar22]

I would agree if any of the system components had been removed or replaced. That will definitely introduce air into the cooling system, creating air bubbles that need to be bled out. With the overflow tank at the high point of the system, removing the cap and adding coolant actually reduces the inherent volume of air in the cooling system. Air, being lighter than liquid, migrates to the high point of the system (the overflow tank.). This limited volume of air is always in the system and provides the necessary expansion space when the system is heated and pressurized. (Boyles Law???) Not necessary to bleed the system when adding coolant.

You literally just explained why it would drop after a drive of it getting to full operating system. It can't"bleed" itself this the thermostat opens up

 

[theDoktor]

Please explain how air got below the thermostat without the system being opened up.

Yes, a thermostat will restrict complete circulation of any air in the system and the coolant until the coolant reaches the thermostat's opening temperature. Once coolant temperature reaches the thermostat opening temperature, full circulation of coolant will occur. A thermostat is used to get the cooling system up to operating temperature faster. This helps reduce emissions and gets operating parts to their design operating dimensions more quickly. A thermostat isn't necessary for an engine to be cooled properly- it just makes it do the job of cooling the engine more efficient and quicker.

When the system is cold, it is still a sealed system if it is in proper operating condition. Coolant level will raise and fall within the properly operating, undisturbed, cooling system as it heats up and cools down. This is the result of the pressure and temperature changes occurring within the sealed system- re: Boyle's Law. Any air induced into the system will always rise to the top of the system unless it gets trapped somewhere (and that can be a real PITA to resolve. DAMHIK) and is typically released from the system thru the overflow tank cap right after the thermostat opens. This air bleeding of the system is done right after the opening up of the cooling system below the system high point (radiator cap- old school, or overflow tank cap- newer stuff), whether for repairs or maintenance and ONLY happens after the lower part of the system get opened to the atmosphere. Once that extra air is removed, no more air will enter or exit the system unless there is a leak somewhere. Opening the overflow tank, hot or cold, does not induce additional air into the cooling system. I don't recommend doing this when it is hot- that's a great way to get burned or worse.

 

[mopar22]

Please explain how air got below the thermostat without the system being opened up.

Yes, a thermostat will restrict complete circulation of any air in the system and the coolant until the coolant reaches the thermostat's opening temperature. Once coolant temperature reaches the thermostat opening temperature, full circulation of coolant will occur. A thermostat is used to get the cooling system up to operating temperature faster. This helps reduce emissions and gets operating parts to their design operating dimensions more quickly. A thermostat isn't necessary for an engine to be cooled properly- it just makes it do the job of cooling the engine more efficient and quicker.

When the system is cold, it is still a sealed system if it is in proper operating condition. Coolant level will raise and fall within the properly operating, undisturbed, cooling system as it heats up and cools down. This is the result of the pressure and temperature changes occurring within the sealed system- re: Boyle's Law. Any air induced into the system will always rise to the top of the system unless it gets trapped somewhere (and that can be a real PITA to resolve. DAMHIK) and is typically released from the system thru the overflow tank cap right after the thermostat opens. This air bleeding of the system is done right after the opening up of the cooling system below the system high point (radiator cap- old school, or overflow tank cap- newer stuff), whether for repairs or maintenance and ONLY happens after the lower part of the system get opened to the atmosphere. Once that extra air is removed, no more air will enter or exit the system unless there is a leak somewhere. Opening the overflow tank, hot or cold, does not induce additional air into the cooling system. I don't recommend doing this when it is hot- that's a great way to get burned or worse.

I didn't see that they just topped it off. I figured they replaced your thermostat

 

[theDoktor]

No problem. I just hope they fix the bloody leak!

 

[Boltsfan17]

Update: Took car in for 40k service. Notified service writer of coolant leak and referenced my research and the numerous posts here about this issue. Told him I strongly believed it to be the thermostat housing and that it should be a covered repair via the drivetrain warranty. Was polite but made it clear I was ready for battle if this was not going to be covered.
Left the car and couple hours later received a call back notifying me it was indeed the thermostat housing and would be covered. My recommendation is to let the dealer know you’ve educated yourself on this issue and make sure the repair will be covered before they do the work. Rather fight for a repair to be covered than get a refund after the fact. Good luck out there and thanks for all that posted here. I had no idea about this issue until I came here.

 

[The Fed]

I had an identical experience with my car.

"Hurr durr, it holds pressure so there's nothing wrong!"

Yeah, ok. It's a supposedly sealed system so that antifreeze is going somewhere, and I shouldn't be having to add coolant every few months on a relatively newer car.

I'm contemplating getting rid of it before it gets truly up there in age. Does anyone know if the R has the same problem?

Yes. Mine does the same thing, but then so did my MK5 and MK4. It's not enough to be of concern to me at the moment. No drips.