GOLFMK8
GOLFMK7
GOLFMK6
GOLFMKV

Failed Thermostat Housing/Coolant Loss Info Gathering

avenali312

Autocross Champion
Location
Mableton, GA
Car(s)
2015 GTI
FYI, document what you find, when you find it, with photos so you can show your dealer.

This. Even though my photos I took were a couple of months apart, it clearly showed a 2" drop in coolant in the bubble under the hood. Even without the drip trail, I think they could have seen a lot just by that.

For example, I showed these that were taken a little less than 2 months apart...



 
Last edited:

ThatWhiteRabbit

Passed Driver's Ed
Location
Lisle IL
Will post on reddit later. This is something I'm following in my own car closely.

For reference, 2017 S, 6MT, currently 32k miles, first noticed a faint coolant smell at about 10k miles. I kept an eye on the coolant and noticed it dropped abruptly my first summer with the car. Had a pressure test done, dealership said it passed and topped the coolant off. The level has remained steady since but I still smell coolant once in a while, under certain conditions.

An indy shop changes my oil/does routine maintenance and they're aware of the issue and are keeping an eye on the thermostat housing--they haven't seen anything yet.
 

Carlosfandang0

Autocross Newbie
Location
UK
Car(s)
2016 3Dr GTi DSG CSG
Mine also passed pressure tests at two different dealerships, after the second time I returned with photos of the dried coolant around the housing (taken from underneath with belly pan removed) and they then replaced it without question!
 

RichardCranium

Ready to race!
Location
Arizona
My 2016 GTI S and my wifes 2015 Jetta SE both have had slight coolant loss/smell. Both were brought to dealer around 35k miles, pressure tested and found no issue. Coolant continues to slowly disappear.

Same story with my 2017 S. I've had to top it off twice now and it probably needs it again at 40k miles. They pressure tested it and said nothing was wrong, yet it's clearly losing coolant.
 

2slowvw

Moderator
Location
VA
Car(s)
2022 Tesla Model 3
DOn't have my paperwork handy right now. But got mine replaced at 59k. Slow leak, saw some dried up fluid on the engine. Usual signs. They replaced it under warranty even though my car is heavily modified.
 

surfstar

Ready to race!
Location
Cali
Not on reddit, this was my Mom's car with the issue:

2015 Golf S 1.8 TSI 2dr
just prior to 60k miles, Aug 2019
dealer said warranty only covered water pump parts
charged her for labor and thermostat housing (came out to effing $1200)

Will be escalating to VW to try to get a reimbursement.
 
Last edited:

jimlloyd40

Autocross Champion
Location
Phoenix
Car(s)
2018 SE DSG
Not on reddit, this was my Mom's car with the issue:

2015 Golf S 1.8 TSI 2dr
just prior to 60k miles, Aug 2019
dealer said warranty only covered water pump parts
charged her for labor and thermostat housing (came out to effing $1200)

Will be escalating to VW to try to get a reimbursement.


That's bull crap. I agree with going to VW. There's lot of posts in the forum where this was covered even shortly after a warranty had expired because of being such a prevalent problem.
 

hooville

Go Kart Newbie
Location
Marietta GA
2016 GTI S 26K

I have added about 1/3 liter annually since buying it new.

Dealer pressure tested the cooling system in January (just before the warranty ended) and it was within spec so no parts replaced but the loss continues...
"Coolant loss is normal with these cars" :rolleyes:
 

Finglonga

Drag Racing Champion
Not on either but mine (2014 GTI PP) was replaced under warranty in 2016 at 36k if I remember correctly. Dealer sent a video of deposits on the sump, it was only losing a tiny bit of coolant.

*edit Thermostat housing leaking was the fault, water pump is the original.





 
Last edited:

Jacobmk7

Go Kart Newbie
Location
NC
Car(s)
2015 GTI S 4dr DSG
Not on either but mine (2014 GTI PP) was replaced under warranty in 2016 at 36k if I remember correctly. Dealer sent a video of deposits on the sump, it was only losing a tiny bit of coolant.





Exactly what mine looked like.
 
Top