2015 Coolant pump/Tstat?

740GLE

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2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
Looking for others experiences, drove the wife’s Passat couple days this week.

So +11K on the clock, NOS that spend two+ years in a dealers lot, this is the first winter with the car.

Outside temps 10-30F, at the beginning of the day car is garaged at 45 or sitting at work in sub freezing temps. This happens with fans on 1-2 temp set to 65 or hvac system all the way off.

Commute is pretty relaxed, 30-40mph with some small hills one or two stop lights. Drive for the 3-5 minutes, the dummy temp gauge start to rise gets to second or third hash mark. Then sits there for less than a minute then falls back to stone cold, where it then starts to climb again in about 2-3 minutes it’s back to second or third mark. Oil temp in the MFD isn’t even registering until gauge is at 4 hash mark.

Do others temp gauge move linearly or to they cycle like I described? I’m aware the coolant loops water pump of the ’15 is a different beast than 12-14 Passat’s. Same commute on my CJAA I was able to get the temp gauge right at 190 when arriving at work, where as the Passat seems a little behind granted it’s dumping more heat into the cabin.
 

rustycat

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Dec 27, 2012
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seattle
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2015 passat sel
Our gauge is uninterrupted in its slow rise to operating temps. And, yes, it's the same car as yours with 8K on the clock.
 

Skimax

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White mts, NH
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97 B4 variant(retired at 330K), 2000 B5 1.8T passat retired, 2013 SE (buyback5/17) 2015 SEL, 2015 E-Golf SEL sold March 2019, 2018 Volt LT and a 2007 PRHT MX5 for fun
Our 2015 NOS SEL with 9.5K does exactly the same thing. Maybe it' a NH thing;) Our cars are in an unheated garage.

It's down hill in every direction from our place and on those -20F or colder days it takes a good 20 miles to get up to normal operating temp. We don't usually use our TDI for short trips especially in the winter. We use our eGolf which shows a reduced range in really cold temps and with winter tires on it but on trips of 25 miles one way or less it works great.
 

adjat84th

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Virginia Beach, VA
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'01 Jetta TDI/'15 Golf TDI
CRUA (EA288 in Golf form) does this as well. It's the effect of the dual stage water pump going from fully closed shroud position to fully open and coolant mixing more thus dropping the temp on the gauge. And, at least in my Golf, the dummy gauge is rather accurate while warming up.
 

BKmetz

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Illinois
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2015 Passat, titanium beige, 6MT
I have a Scangauge-II so I ignore the almost useless dash gauge. On the Scangauge I monitor 4 data points; EGT temp, DPF temp, coolant temp, and turbo boost. This is so I can monitor regens accurately.

The dash gauge is highly buffered. It shows a faster temperature gain than the scangauge between lowest hash mark to the 190F mark by about 30F. When the engine is at normal operating temp, the dash gauge and scangauge are within 5F of each other. The scangauge is always at 190F, temp rise of no more than 10F, 190F to 200F, while the dash gauge will show 190F, maybe rise to 195F.

The water pump on the CVCA engine, besides a thermostat, has shutters on it that redirect flow from the different cooling sub-loops; EGR cooler, oil cooler, and intercooler. The CVCA engine also has coolant passages around the exhaust ports for quicker warm up. What I believe you are seeing is after the engine is starting to warm up, the sub-loops get heat, then the thermostat is starting to open up and direct normal flow to the radiator.

:)
 
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Skimax

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I have a Scangauge-II so I ignore the almost useless dash gauge. On the Scangauge I monitor 4 data points; EGT temp, DPF temp, coolant temp, and turbo boost. This is so I can monitor regens accurately.

The dash gauge is highly buffered. It shows a faster temperature gain than the scangauge between lowest hash mark to the 190F mark by about 30F. When the engine is at normal operating temp, the dash gauge and scangauge are within 5F of each other. The dash gauge is always at 190F, temp rise of no more than 10F, 190F to 200F, while the dash gauge will show 190F, maybe rise to 195F.

The water pump on the CVCA engine, besides a thermostat, has shutters on it that redirect flow from the different cooling sub-loops; EGR cooler, oil cooler, and intercooler. The CVCA engine also has coolant passages around the exhaust ports for quicker warm up. What I believe you are seeing is after the engine is starting to warm up, the sub-loops get heat, then the thermostat is starting to open up and direct normal flow to the radiator.

:)
I didn't know the intricacies of the cooling system but what I'm seeing on the temp gauge in the instrument cluster correlates to what you say.

The engine in my experimental aircraft is a Honda Fit engine converted to aircraft use, a Viking 110, and it has a thermostat from an Aprilla motorcycle, I can tell when it opens by closely watching the temp readout on the EMS(engine monitoring system) but it is certainly a linear progression.
 
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BKmetz

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Illinois
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2015 Passat, titanium beige, 6MT
The oil temperature reading on the MFD reads *** until the oil temperature reaches around ~120F to 125F. I watched the oil temp today and dash gauge and scangauge were fully warmed up to 190F before the oil temp reading went from *** to 125F on the MFD. Then it rises to 205F rather quickly. Once the oil is at normal temperature it's usually 5F to 15F higher than the coolant temperature.

:)
 
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740GLE

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2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
The oil temperature reading on the MFD reads *** until the oil temperature reaches around ~120F to 125F. I watched the oil temp today and dash gauge and scangauge were fully warmed up to 190F before the oil temp reading went from *** to 125F on the MFD. Then it rises to 205F rather quickly. Once the oil is at normal temperature it's usually 5F to 15F higher than the coolant temperature.

:)

See that's where we're different, what were your outside temps while starting?

I start seeing oil temp go from --- to 120 when the dummy temp coolant gauge is at approx 9-10 oclock position, well far from the normal 190f. It's not until the coolant shows 190f does the oil temp indicate 160-170f, showning the oil temp tracks the coolant temp much more closer.

What you just described is very similar to my TSI in the alltrack, coolant shows 200f within 2-3 minutes, where as oil temp takes 7-10 minutes to start registering 120f.

I'd hate to think those that have similar expressiveness of myself have busted coolant/tstat pumps. it seems like that second coolant loop is opening up too soon, maybe the idea is that the coolant will actually start heating up the oil.
 
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740GLE

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NH
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2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
Not to bump a dead thread, but took the Passat on another work trip last Friday with torque hooked up. It was about 10-7F out along the commute, but she was garaged at about 40-45.

Via torque, I noticed the coolant climbed to about 140f and then shot down to about 120f, the dummy gauge did similar, got to about 9-10 o'clock, then went down to stone cold, to only start climbing again.

Did get oil and coolant up to 180ish in about 15 min of steady 40-50mph driving.
 

251

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May 11, 2002
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NW IN
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2015 Passat TDI SEL
My 2015 Passat TDI SEL always warms up slow and steady on the temperature gauge. Have never seen the gauge drop during warm up to normal operating temperature.
 

adjat84th

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Virginia Beach, VA
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'01 Jetta TDI/'15 Golf TDI
Not to bump a dead thread, but took the Passat on another work trip last Friday with torque hooked up. It was about 10-7F out along the commute, but she was garaged at about 40-45.

Via torque, I noticed the coolant climbed to about 140f and then shot down to about 120f, the dummy gauge did similar, got to about 9-10 o'clock, then went down to stone cold, to only start climbing again.

Did get oil and coolant up to 180ish in about 15 min of steady 40-50mph driving.
This happens in my '15 Golf as well. Must be the sleeve coming off the impeller allowing coolant flow to increase.

Sent from my Pixel 2 using Tapatalk
 

jrm

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Oregon
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2013 Passat SE with nav (totaled)
my new to me 15 does the same, takes 5 miles @ 70MPH to get warm on the gauge and produce cabin heat. My old 2013 CKRA only took 2 miles before it was fully warm with good cabin heat
 

740GLE

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NH
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2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
my new to me 15 does the same, takes 5 miles @ 70MPH to get warm on the gauge and produce cabin heat. My old 2013 CKRA only took 2 miles before it was fully warm with good cabin heat
Thats the thing warmish air is felt when coolant gets about 100-120F and stays warmish say 2-3 min of driving and wont' get hottish until coolant is 180F, which in total time is about the same as our '12.
 

Fixmy59bug

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Aug 1, 2009
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Las Vegas, NV
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2015 Passat TDI SE
my new to me 15 does the same, takes 5 miles @ 70MPH to get warm on the gauge and produce cabin heat. My old 2013 CKRA only took 2 miles before it was fully warm with good cabin heat
I noticed that as well...

The 2013 I had was really good about quick cabin heat, where as the 2015 is a lot slower. I wonder if the ceramic heater is less efficient (or at less power) than the previous years.
 

740GLE

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NH
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2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
I don't think the '15 Passats have the grid heaters, I never hear the relay click like our '12, no matter what temp/HVAC settings are.
 

LeeM

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Jan 26, 2003
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Hagerstown,MD
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2015 Passat SE, 2002 Jetta Reflex Silver
When I go to Parts Vortex, it lists the same components in the HVAC system for the 2012-2015 Passat.
 

740GLE

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NH
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2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
Wife said she'd rather freeze than have that on her car. Amazingly enough it was on her car for 4 days before she noticed it, later sold for a loss of $30.

Yesterday, it was a high of 0F out, we drove the Passat to a late lunch 25 miles away, garage was 38-42F. Oil temp never reached 190F, if we kept the HVAC at 3 fan and temp of anything above 68F. But the cabin heat was def keeping us warm. Coldest the oil got was 160F in driving/coasting down a hill.

I will state the coolant gauge stayed rock steady at 190F after 10-15 minutes.

Only climbng
 

jrm

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Oregon
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2013 Passat SE with nav (totaled)
I notice I do get heat but only at the 3 light level, 2 nothing 3 i do get the 2013's style luke warm
 

LeeM

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Jan 26, 2003
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Hagerstown,MD
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2015 Passat SE, 2002 Jetta Reflex Silver
I have a winter front on my 2015. Last night with a 6° F air temp, and not running the heater, it took 5 miles at 45 mph for the coolant gauge to indicate 190° F. The oil temp reading on the MFD was 123° F and at 13 miles it was 190° . Somewhere around an oil temp of 165° F the heat was turned on to de-fog the windows and begin to thaw the driver. With the manual temp knob set to the 2 o'clock position it still takes a while to warm things up.
 

740GLE

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On my CJAA Jetta, I used to leave the heater fan off until the coolant showed 190f, now I'm just leaving the fan on 1 or 2 and max the heat temp and dial back once cabin is comfortable.

Winter front will def help that 6L of oil warm up faster.
 
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