Thermostat replacement

2012jsw

Well-known member
Joined
Nov 20, 2020
Location
Socal
TDI
2012 jsw, 2010 jsw
Sorry, been busy!
I think I put the idparts one in, but I’m not 100% positive, I’ll have to look at my receipts. Generally Idparts lists most of their stuff as “oe”
It was a pain, but truly not that bad, and second time around will be much easier, so if I have an issue with the new one I can probably get it replaced in 2-2.5hrs.
I don’t have any way to monitor temp other than the factory dash gauge. I was just replacing mine since the system was already drained for the TB and I figured with 150k miles I might as well
On a side note, has anybody had issues getting things shipped from “usp motorsports” I ordered my RT vcds like 2 - 3 weeks ago and their website claimed it was in stock and ready to ship. 2 emails and 2 phone calls later and I still don’t have it. Car is sitting and waiting for that so I can prime the fuel system.
Do any of our vendors have a new 3 vin sitting on the shelf that can ship
 

super1

Veteran Member
Joined
Apr 19, 2010
Location
NY
TDI
none
Sorry, been busy!
I think I put the idparts one in, but I’m not 100% positive, I’ll have to look at my receipts. Generally Idparts lists most of their stuff as “oe”
It was a pain, but truly not that bad, and second time around will be much easier, so if I have an issue with the new one I can probably get it replaced in 2-2.5hrs.
I don’t have any way to monitor temp other than the factory dash gauge. I was just replacing mine since the system was already drained for the TB and I figured with 150k miles I might as well
On a side note, has anybody had issues getting things shipped from “usp motorsports” I ordered my RT vcds like 2 - 3 weeks ago and their website claimed it was in stock and ready to ship. 2 emails and 2 phone calls later and I still don’t have it. Car is sitting and waiting for that so I can prime the fuel system.
Do any of our vendors have a new 3 vin sitting on the shelf that can ship
did you go to the VCDS Ross Tech site?
 

DrGERTol

Veteran Member
Joined
Aug 27, 2020
Location
NW OH
TDI
2011 Golf Variant (JSW) 6MT
...
Do any of our vendors have a new 3 vin sitting on the shelf that can ship
... would be my two choices for this. --g
 

borninabus

Veteran Member
Joined
Feb 18, 2020
Location
Arizona
TDI
-2013 JSW 6MT- -2006 Jetta DSG-
just had mine done @ my local indy shop using all genuine parts.
$822 all in.

03L121111AM thermostat: $131
03L121065T pipe: $63
R&R stat & pipe: $588
coolant: $40
 

Tuheeden

Veteran Member
Joined
Sep 18, 2022
Location
North Carolina
TDI
2013 & 2014 Jetta sportwagon
I have done 2 of them and I bought the Mahle thermostat for like $51 and used a wobbly socket and extension to remove the 2 bolts without removing the oil filter housing. I do recommend buying the tube cause it can easily break. It's a solid 3 to 5 hours if your doing it yourself for sure.
I broke the oil dipstick tube which of course had to be ordered but that was my fault!
As others have said, don't rely on the stock temp guage. Use an OBD or VAGS reader to get the real temp. It should reach 185f+ when driving if it's working. If the temp only reaches 165f and then drops, it's time to replace it.
 

DriverJon

Veteran Member
Joined
Jan 22, 2011
Location
Irvine, CA
TDI
2010 Jetta TDI, 6M
Hmmm.... Still trying to judge shop's knowledge, as well as pricing. I have one estimating it as $480, another at $580, then I've had a few close to a grand, and the dealer at the $2500 mark. Have dropped one on bad feelings, when I got a large amount of talk like "can't tell you how much, need to get it in here to see how many other things might be wrong as well". I understand that basic concept.... but if you're going to go on so long about what else you will (might) find out wrong with the car... you're gonna get me nervous.

I had one shop that sounds like they may know their stuff, but was quoting me $220 for the thermostat, stating that it's two parts, $88 for the internal actual thermostat, and $130ish for the "housing" that it goes into. First time I've heard that it's not a single, multi hose bearing plastic part, with a thermo inside it. Kinda wondering about these guys. I see $130 for oem at ID parts, vs a $39 aftermarket also available.

Also, to the earlier convo about temp gauge readings, I channeled my OCD one day and mapped out what I was reading on VCDS vs what I see on my gauge, warming it up in the driveway:


Temp gauge notches VCDS temp
coming off 0 123F
1132F
1.5138.2F
2143.4F
3154.4F
3.5162F
4167F

4 is the gauge indicating "190F"
I didn't get it hot enough to move above "190F" so nothing measured. I have seen others say it's something like 205F.

FWIW...

Another thing of note, I had a lot of the symptom, i.e. floating around notch 2-3.5 and never getting to full temp, for many months, WITHOUT getting the code. I did eventually get the thermostat code a few times, read in VCDS. The error comments sound like it tries to see certain temps by certain times, and it seems that you can have a pretty slow/low warmup profile and the ECU can miss it.
 
Last edited:

Tuheeden

Veteran Member
Joined
Sep 18, 2022
Location
North Carolina
TDI
2013 & 2014 Jetta sportwagon
The stock guage reads 190 degrees exactly as the temperature reaches 167. If the temp drops to 165 the stock needle will drop slightly below the 190 mark. The proper operating temperature is 87c or 188f. All engines benefit from actually reaching and maintaining proper operating temperature.

As for thermostats, since it's quite a job, I don't use 'no name' parts. Get a decent brand name or even stock is ok.

As for shops, they often look up the job hours incorrectly. If they say they can do it in 2 hours, they are mistaken. A shop that actually knows how to do it will likely charge $600 to $800. I just had a dealer quote me $1297 to do one. Now I just do it my6for the proof the part and some antifreeze! Of course book the whole day.....
 

DriverJon

Veteran Member
Joined
Jan 22, 2011
Location
Irvine, CA
TDI
2010 Jetta TDI, 6M
Book time is 2.7hr. I always replace the plastic pipe that is prone to breaking, too. I think we charge 3.0hrs, we are currently $150/hr.
just had mine done @ my local indy shop using all genuine parts.
$822 all in.

03L121111AM thermostat: $131
03L121065T pipe: $63
R&R stat & pipe: $588
coolant: $40
Update on this... Was going to go for the shop that phone quoted me $800-900, but the other place I'd used said "$480 out the door!!" despite my numerous checks of "it's the TDI, you know... they are different... you're sure about that price???".

Well... after a lot of waiting for parts ordered, and extra day for the oil filter housing gasket to get ordered... and because I asked for the hard pipe to be done... finally there was a mention of "$590, out the door" And, at the end, they said it's gonna be $1200!! "You know, that pipe, goes from the front to the back of the engine..." I uh, expressed my displeasure. And quoted their earlier prices back. After a day or so, they offered to cut $500 off the job.

Kicker here is I got a P00AF, the day before I brought it in. They seem to finally have diagnosed what I was thinking (hadn't read fully in, or time to test past looking at hoses and sucking on the seemingly leaky actuator) "intermittently" leaky actuator. Which they want $968 more to replace. It wouldn't go into limp mode, so they couldn't diagnose it and did the thermostat replacement first. I wondered if you could diagnose it if it WAS in limp mode? They say actuator leaks, and sometimes dosen't... which doesn't sound quite right. I wonder if that's an accurate diagnosis.

Oilhammer, what kind of time charge does that have? I'd guess a lot lower than that, since the part is $176 at ID parts... Is that more like the labor to pull the turbo and clean the vanes? (why am I worried they'd charge me for the latter and just do the former?)

I'd have the car home and do it myself by the end of today, but I have a cross state vacation trip to make in 9 days... GRRRR.... just worrying about how fiddly it sounds, getting at the stop screw, and bad clearances. I do have the Ross-Tech, for diagnosing and adjustment.
 
Last edited:

Tuheeden

Veteran Member
Joined
Sep 18, 2022
Location
North Carolina
TDI
2013 & 2014 Jetta sportwagon
Update on this... Was going to go for the shop that phone quoted me $800-900, but the other place I'd used said "$480 out the door!!" despite my numerous checks of "it's the TDI, you know... they are different... you're sure about that price???".

Well... after a lot of waiting for parts ordered, and extra day for the oil filter housing gasket to get ordered... and because I asked for the hard pipe to be done... finally there was a mention of "$590, out the door" And, at the end, they said it's gonna be $1200!! "You know, that pipe, goes from the front to the back of the engine..." I uh, expressed my displeasure. And quoted their earlier prices back. After a day or so, they offered to cut $500 off the job.

Kicker here is I got a P00AF, the day before I brought it in. They seem to finally have diagnosed what I was thinking (hadn't read fully in, or time to test past looking at hoses and sucking on the seemingly leaky actuator) "intermittently" leaky actuator. Which they want $968 more to replace. It wouldn't go into limp mode, so they couldn't diagnose it and did the thermostat replacement first. I wondered if you could diagnose it if it WAS in limp mode? They say actuator leaks, and sometimes dosen't... which doesn't sound quite right. I wonder if that's an accurate diagnosis.

Oilhammer, what kind of time charge does that have? I'd guess a lot lower than that, since the part is $176 at ID parts... Is that more like the labor to pull the turbo and clean the vanes? (why am I worried they'd charge me for the latter and just do the former?)

I'd have the car home and do it myself by the end of today, but I have a cross state vacation trip to make in 9 days... GRRRR.... just worrying about how fiddly it sounds, getting at the stop screw, and bad clearances. I do have the Ross-Tech, for diagnosing and adjustment.
I just did 2 of them in the last week. Happy to share tips and second one was done in less than 3 hours. PM me if you get into it and have questions!
 

gmcjetpilot

Veteran Member
Joined
Aug 18, 2008
Location
Memphis TN
TDI
2010 JSW TDI DSG Matalic Grey
So GLAD I read this before posting. I am facing a thermostat issue (but I am still going through the stages of denial). I use to read a solid 190-192F. Now I read 177-181F, with outside temps of 75F. I find it hard to believe this is an issue, but it is summer. This would not be good in cold weather. I do not notice it taking longer to warm up.

My question (please correct me if wrong), since it is summer 75F OAT or hotter (much hotter), and doing mostly long road trips at interstate highway speeds,, is 177F a problem? I can not believe -13F cooler water temp (per OBDII gauge) is critical. If I did not have gauge I would not even know, no warning or fault code and OEM dash water temp reads 12 O'clock all day long (yes I know it is buffered). If that is NORMAL than that is normal. Is this going to affect REGEN?

I plan on changing the thermostat in the fall, but I am going on road trips soon. I am going to order the OEM parts soon. I don't plan on taking front end of car off for "service position",
 
Last edited:

Tuheeden

Veteran Member
Joined
Sep 18, 2022
Location
North Carolina
TDI
2013 & 2014 Jetta sportwagon
So GLAD I read this before posting. I am facing a thermostat issue (buy I am still going through the stages of denial).
. I use to read a solid 190-192F from the new. Now I read 177-181F, with outside temps of 75F.

My comment (please correct me if wrong), since it is summer 75F OAT or hotter (much hotter), and doing mostly long road trips at interstate highway speeds,, is 177F a problem?

I plan on changing the thermostat. In fact I am going to order the OEM one... I see they are $134 (AM part number). Not sure about the plastic pipe if I have to take more stuff out. I don't plan on taking front end of car off for "service position",
So there are 2 considerations: 1 - How long is it taking to GET to 177F? (at the outside temp it should be 5-7 minutes if driving) and then will it maintain that temperature when you NOT on the highway. It was taking 20 minutes of driving for one of mine to GET to 170F, now its 5 minutes.
Just a few notes if you do it yourself: If you go under the car OTHER than to remove the skidplate - your doing it wrong! - There is one bolt toward the back of the engine above the transmission that secures the hard plastic pipe in place - you MUST remove this or you will break the pipe when trying to get the old thermostat out

So the short answer is that 177F on the highway is probably fine but the warm up times are likely very long and that leads to additional wear and loss of some economy (and can assist in clogging the DFP if bad enough). So its not an emergency but put it on the list this year!
 

borninabus

Veteran Member
Joined
Feb 18, 2020
Location
Arizona
TDI
-2013 JSW 6MT- -2006 Jetta DSG-
come to realize i ran mine around for the better part of 2 years with a failed stat. regens were weird sometimes (rough running) and you could always tell when you were driving when one was happening. it would be really jerky when you got on the go pedal. other than that, no problems here (where it's always warm).
 

gmcjetpilot

Veteran Member
Joined
Aug 18, 2008
Location
Memphis TN
TDI
2010 JSW TDI DSG Matalic Grey
So there are 2 considerations: 1 - How long is it taking to GET to 177F? (at the outside temp it should be 5-7 minutes if driving) and then will it maintain that temperature when you NOT on the highway. It was taking 20 minutes of driving for one of mine to GET to 170F, now its 5 minutes.
Just a few notes if you do it yourself: If you go under the car OTHER than to remove the skidplate - your doing it wrong! - There is one bolt toward the back of the engine above the transmission that secures the hard plastic pipe in place - you MUST remove this or you will break the pipe when trying to get the old thermostat out

So the short answer is that 177F on the highway is probably fine but the warm up times are likely very long and that leads to additional wear and loss of some economy (and can assist in clogging the DFP if bad enough). So its not an emergency but put it on the list this year!
THANKS.... So warm up is not bad with warm OAT, say 75F or higher. I have time to let it idle for 5 mins before heading out. It is up to or near 177F in a few miles or 5 more mins.... However SUMMER is here with a vengeance.

Today I did 80 miles, 40 out and 40 back with OAT ranging from 94F to 98F. I saw water temps from 181F to 191F, Max water temp 195F for a short time. Most of the time it was 188F. On way home later in day with OAT near 100F, on freeway 70 mph, WT was solid 191F. I was also running AC. The NORM was 190-192F even w/ cool OAT Temps.

EGT would pop up to Approx 1250F and even 1350F. Regens are short (if that was indeed a Regen). However short REGENS became common after the EPA MODIFICATION 4 yrs ago. Before the Mod, REGEN's while driving were longer and less frequent. Now they are short and Freq. I know of now other way to detect a REGEN while driving other than EGT. When REGENS were long you might see Avg MPG go down a 1/10th. If stopped the high idle, smell, are tell tales of REGEN.

Bottom line I feel comfortable deferring the REPAIR. Winter is different story, it has to be done. Hot summer OAT, say 85F or hotter it should not cause any issue. I have no faults or caution lights.... Before fall the repair will be done. Besides it too hot in garage to work.

PS: I still want to drive with the laptop and VAGCOM connected to see if WT matches what the OBDII Scangauge II shows. If ONLY using OEM dash water Temp gauge I'd have no idea car was running cooler than the normal temp it has run last 10 years. I am now sure the thermostat is not operating properly. However the temp probe could go bad I assume.
 
Last edited:

Cha2ga

Veteran Member
Joined
Jun 9, 2013
Location
Easley, SC
TDI
'11 JSW
This is a very good thread with lots of info. I need to do this repair and am dreading it.
 

JELLOWSUBMARINE

Veteran Member
Joined
Mar 3, 2014
Location
yes
TDI
2011 Jetta Sportwagen, 6M, red/tan, navi, pano, 83 5m diesel pickup, 82 p/u trailer,.04 5.5 TDI Passat wagon (gone), 80,81,82 diesel p/u (gone), 80,82 sportruck (gone), 59 passthru bus (long gone), 79&87 westy (gone), 57 baja bug (long gone), 73 914
Book time is 2.7hr. I always replace the plastic pipe that is prone to breaking, too. I think we charge 3.0hrs, we are currently $150/hr.
O.K. 2.7 hrs... lets just round up to 3.0 hrs. Fair enough. no issue
But all I've ever seen were quotes north of $1k to $1.2k in Ca. but obviously other states also.
That would be up to 250 to 300% overcharge. A go somewhere else quote.
I've never seen the automotive field (in general dealerships) so lazy/corrupt/greedy
 

JELLOWSUBMARINE

Veteran Member
Joined
Mar 3, 2014
Location
yes
TDI
2011 Jetta Sportwagen, 6M, red/tan, navi, pano, 83 5m diesel pickup, 82 p/u trailer,.04 5.5 TDI Passat wagon (gone), 80,81,82 diesel p/u (gone), 80,82 sportruck (gone), 59 passthru bus (long gone), 79&87 westy (gone), 57 baja bug (long gone), 73 914
87C- 102C (the CJAA uses a staged thermostat).
That would be *215f my 11 NEVER went over *185 (110 OAT often), right away, every time. I think it ran too cold though
 

McGuirk

Veteran Member
Joined
Aug 30, 2012
Location
Florida
TDI
Audi A3 TDI
Just did mine on the A3. Nightmare but not as bad as an evaporator. Had the whole front end off and it was still difficult.
 

Cha2ga

Veteran Member
Joined
Jun 9, 2013
Location
Easley, SC
TDI
'11 JSW
you must pull the oil filter housing to undo the bolt behind it which secures the plastic pipe to the block
I've seen where quite a few people have had success with removing the bolt without removing the housing. Assuming that method, can the pipe be replaced without removing the housing?
 

lemoncurd

Veteran Member
Joined
May 24, 2019
Location
Eastern CT
TDI
2013 CJAA GTB2266
I've seen where quite a few people have had success with removing the bolt without removing the housing. Assuming that method, can the pipe be replaced without removing the housing?
see:

i find it extremely doubtful you can swap the plastic tube with the oil cooler in place.
 

mikerob97

Veteran Member
Joined
Feb 17, 2002
Location
Cary, NC
TDI
2014 Jetta Sportwagen
Slightly off topic, I am planning to replace the T-Stat while while changing the T-Belt, upgrading to the CP3 HPFP and converting to the CR170 turbo. And after reading this thread, looks like I should also be replacing the plastic Coolant Pipe.

Questions:
1. Is there an advantage to replacing T-stat and coolant pipe while doing the other work as described above, or is the T-Stat & Coolant Pipe largely an independent project?

2. When removing the Oil Filter Housing to get to the T-stat, is there a gasket between the engine block and the oil filter housing that should be replaced? Anyone have a part number? (vehicle 2014 Jetta Sportwagen Tdi, 6 speed)

This forum is an invaluable source of information.

Thanks,
Mike
 

DrGERTol

Veteran Member
Joined
Aug 27, 2020
Location
NW OH
TDI
2011 Golf Variant (JSW) 6MT
...
2. When removing the Oil Filter Housing to get to the T-stat, is there a gasket between the engine block and the oil filter housing that should be replaced? Anyone have a part number? (vehicle 2014 Jetta Sportwagen Tdi, 6 speed)
...
Looks like you want p/n 045115441, #9:

--g
 

Wilkins

Veteran Member
Joined
Aug 19, 2005
Location
British Columbia
TDI
05 Jetta Wagon 5sp, 10 Sportwagen 6MT
Is there an advantage to replacing T-stat and coolant pipe while doing the other work as described above, or is the T-Stat & Coolant Pipe largely an independent project?
Only commonality is draining the coolant. I did both of mine at the same time, having the front end in service position might help a little with access, not sure.
 

McGuirk

Veteran Member
Joined
Aug 30, 2012
Location
Florida
TDI
Audi A3 TDI
Only commonality is draining the coolant. I did both of mine at the same time, having the front end in service position might help a little with access, not sure.
Service position will help. I did mine with the front end off and I don't want to think about doing it without at minimum service position. It is a little bit helpful having the cp4 removed as well. Gives you some more elbow room.
 

mikerob97

Veteran Member
Joined
Feb 17, 2002
Location
Cary, NC
TDI
2014 Jetta Sportwagen
Service position will help. I did mine with the front end off and I don't want to think about doing it without at minimum service position. It is a little bit helpful having the cp4 removed as well. Gives you some more elbow room.
Only commonality is draining the coolant. I did both of mine at the same time, having the front end in service position might help a little with access, not sure.
Thanks for your replies. Noticed both of you used the term Service Position, I am not familiar with this term. What is this?
 

McGuirk

Veteran Member
Joined
Aug 30, 2012
Location
Florida
TDI
Audi A3 TDI
It's when you use extended bolts to slide out the front end as much as possible without disconnecting the coolant hoses or the refrigerant lines. Of course there is a service manual procedure step by step that you can follow for this. Pro tip: don't forget to disconnect the front crash sensors. Ask me how I know.:(
 
Last edited:

mikerob97

Veteran Member
Joined
Feb 17, 2002
Location
Cary, NC
TDI
2014 Jetta Sportwagen
This is fantastic! I did not know about the Service Position.

Watched several videos. Doesn't look too bad. Need to locate some long bolts to thread into the mount points. One of the videos referenced using a 10mm, 1.5pitch x 100mm in length. Can anyone verify if this is correct?
 
Top