Heat Only on Driver Side - clogged heater core

nord

Veteran Member
Joined
Mar 5, 2010
Location
Southern Tier NY
TDI
All turned back to VW. Now a 2017 Hundai Tuscon. Not a single squalk in 10k miles.
Nope, you aren't good even though you may have heat. Orange coolant is contaminated. Whether the flush was incomplete or even done is now in question. I hate to say it but "mechanics" are notorious for ignorance or cutting corners. Leaving orange coolant is very telling.

You do realize that the main cooling system and the EGR system share the same coolant but are distinct circuits, don't you? I would suspect that you got a "quickie" flush which left the EGR circuit untouched. (Very easy to overlook if you don't know the system, or don't much care.)

Notice with my method that you vacuum out as much contaminated coolant as possible, then refill with pure water. The car is then driven and brought to normal operating temp. This insures that clean water reaches and flushes the EGR system. You'll further note that the procedure is repeated until all you get is clean water when you vacuum the reservoir. Usually about three cycles in my experience.

The last step will be to vacuum as much clean water out of the system as possible. Bring the coolant level back up with new coolant and you'll be very close to a 50/50 mix. Run the car and recheck the mix. If slightly off, then vacuum a bit out of the reservoir and refill with water or coolant depending which is needed for 50/50 as specified.

Or... Run until the problem reappears and let your mechanic do it all over again. Maybe not the best plan but perhaps a lesson taught as changing the core is no picnic.
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
Depending on how a person sees color and the viewing angle, the coolant could look orange or pink. I describe G12 as being nuclear pink (with a hint of orange at some angles), whereas G13 is more purple.
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
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Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
Also nord, as far as I know, the main coolant is what flows through the EGR cooler. Perhaps you're thinking of the intercooler circuit?
 

nord

Veteran Member
Joined
Mar 5, 2010
Location
Southern Tier NY
TDI
All turned back to VW. Now a 2017 Hundai Tuscon. Not a single squalk in 10k miles.
Correct! Brain fart I guess. My point, though, stands. The entire system needs flushed and it's almost impossible to do without pulling a lot of plumbing on one hand or flushing per my method on the other.

On the subject of an orange coolant tint, this is why I stressed cleaning the reservoir. Even a slightly contaminated and stained reservoir will cause the pink to go slightly to the orange at least to the eye. Best to siphon coolant out of the tank into a clear glass container to have a look.

So once again... Any orange discoloration is an indication that the system is contaminated. This is the reason the car must be driven for a couple of miles while up to operating temp between flushes until only clear water remains in the system. Only then will the coolant be a bright pink color and not take on an orange tint for the final fill.

Given that there is no easy way to disconnect and flush the system from the bottom side of the car and that we're dealing with two distinct systems sharing the same coolant, I tend to favor the topside flush. I tried the bottom flush on one of our cars and about the best I can share is that I wore and tasted a lot of coolant, and that the flush was unsuccessful. It was very frustrating at minimum.
Topside was quick and easy by comparison.

One last point... The vacuum causes more turbulence than merely cycling clean water through the system. It seems to dislodge more contamination than other methods and allows the clean water to suspend these particles for removal. Water will probably be heavily contaminated for the first two cycles. The third will often be clean. The reservoir will become badly stained and will need cleaning after the last cycle of clean water.
 

bfbay

New member
Joined
Jan 11, 2016
Location
missouri
TDI
2014 passat tdi se
I'm on my second replacement core, and I still don't think things are right. I had the core replaced for the second time 3 weeks ago. Took it back to the dealer after 1 week because I was still getting low heat out passenger side after the core replacement. They ended doing something with the egr cooler and flushing the cooling system. I think they replaced the core without getting the junk out of the cooling system first..

Anyway, I'm getting heat, but the temperature gradient from left to right is 170, 147, 126, 110 when running heat with high fan out of the vents. Car was heated up, vents were all open.

What is the normal temp for the passenger side vent when running highest fan setting and hottest thermostat setting?
 

bustNfuel

Veteran Member
Joined
Sep 7, 2002
Location
Raleigh, NC
TDI
Sold: 13 Passat SEL TDI
Mine was replaced under warranty about a year ago.

The temps from my vents at full hot, fan on high and engine up to normal operating temp and outside air temp in the upper 70's just the other day:

160/160/150/130

...using a Raytek hand-held infrared thermometer.
 

Rico567

Top Post Dawg
Joined
Jun 13, 2003
Location
Central IL
TDI
2013 Passat TDI SEL Premium (Turned in 7/7/18)
Had mine replaced last winter under the extended warranty after a trip to VA where the passenger side was somewhat chilly. If there are any problems again this winter = another core.
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
I'm on my second replacement core, and I still don't think things are right. I had the core replaced for the second time 3 weeks ago. Took it back to the dealer after 1 week because I was still getting low heat out passenger side after the core replacement. They ended doing something with the egr cooler and flushing the cooling system. I think they replaced the core without getting the junk out of the cooling system first..

Anyway, I'm getting heat, but the temperature gradient from left to right is 170, 147, 126, 110 when running heat with high fan out of the vents. Car was heated up, vents were all open.

What is the normal temp for the passenger side vent when running highest fan setting and hottest thermostat setting?
You should be able to get at least 150F from all of the vents at full operating temperature.
 

jrm

Veteran Member
Joined
Jul 24, 2013
Location
Oregon
TDI
2013 Passat SE with nav (totaled)
mine is for sure plugged, I replaced the coolant via the shop vac method Nord did, helped a bit but not much. On a crisp day mine are 160,98,52,40 and wont de-ice the window on the passenger side so when driving in snow, we turn the heat completely off so the window freezes and the snow will not stick to it. works great, buuuut wife isn't on board and wants a new Toyota hilander :(
 

767wrench

Veteran Member
Joined
Jul 25, 2012
Location
Ohio
TDI
1981 Rabbit Pickup
mine is for sure plugged, I replaced the coolant via the shop vac method Nord did, helped a bit but not much. On a crisp day mine are 160,98,52,40 and wont de-ice the window on the passenger side so when driving in snow, we turn the heat completely off so the window freezes and the snow will not stick to it. works great, buuuut wife isn't on board and wants a new Toyota hilander :(
One more factor in my decision to abandon ship! I knew my car was on coolant system life support. I had installed an filtration system and green coolant and it still was turning dark orange although no more sediment and I had good heat. But there were so many coolant hoses between the factory ones, frost heater, and filter that things were chafing and I was constantly inspecting for chafed lines.
 

danko0

New member
Joined
Nov 8, 2017
Location
Bulgaria
TDI
Passat TDI
HI guys, It`s really a long topic, so I believe it`s best to ask :) I`m having Passat b7, with the same issue as all do no heating, so I`m pretty sure it`s the heat core I need to replace. The question is do I need to disassemble the dash ? or the replacement is done from under the driver dash part.

P.s. for some reason I`m not seeing the pics in the topic, so please excuse me if it`s shown there.

Thanks in advance.
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
HI guys, It`s really a long topic, so I believe it`s best to ask :) I`m having Passat b7, with the same issue as all do no heating, so I`m pretty sure it`s the heat core I need to replace. The question is do I need to disassemble the dash ? or the replacement is done from under the driver dash part.

P.s. for some reason I`m not seeing the pics in the topic, so please excuse me if it`s shown there.

Thanks in advance.
I don't know if the B7 (European Passat) is laid out differently than the NMS (North American Passat). In the NMS, heater core access is right next to the accelerator pedal.
 

Bearsvw

Well-known member
Joined
Oct 11, 2016
Location
Orleans ont
TDI
2013 passat highline loaded
Had the heater core replace January of 17 it worked great last winter but now no heat on passenger side again
 

740GLE

Top Post Dawg
Joined
Aug 19, 2009
Location
NH
TDI
2015 Passat SEL, 2017 Alltrack SE; BB 2010 Sedan Man; 2012 Passat,
^^^and...has the real B7 been affected by the heater core issues???
Prob not due to the fact they don't have to meet the same emissions (NOx ) requirements and they probably don't use and abuse the coolant system as much.
 

Bearsvw

Well-known member
Joined
Oct 11, 2016
Location
Orleans ont
TDI
2013 passat highline loaded
Well heater core replaced today again. I have heat again. They ordered the parts for the add blue tank. It's being replaced next.
 

Rico567

Top Post Dawg
Joined
Jun 13, 2003
Location
Central IL
TDI
2013 Passat TDI SEL Premium (Turned in 7/7/18)
We did a road trip yesterday starting out in -6F temperatures, heater core that was replaced in the winter of '14 under the extended warranty is still working fine. Let's hope this means it'll hold up until we turn the car in next December.....
 

Bearsvw

Well-known member
Joined
Oct 11, 2016
Location
Orleans ont
TDI
2013 passat highline loaded
I'm on my 3rd core. Im at dealer now waiting to see. The warranty is good till 2021 or 200000km. But that atlas us looking nicer and nicer every time I'm here
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
Heat is now gone again. It's worse than before the heater core replacement last week.
Are they completely flushing your cooling system? They should run a flushing agent and several purges with water. I would also request that they refill the system with G12 instead of G13, although that might be hesitant to do that if their instructions specify to use G13.
 

Bearsvw

Well-known member
Joined
Oct 11, 2016
Location
Orleans ont
TDI
2013 passat highline loaded
They said they did two flush and said doesnt matter what coolant is used.
So had car checked.
I was told car is doing its job it has enough heat considering the temperature outside That it's the norm with the design of the air box to be cooler on the passenger side. We went back and forth with cooler and down right cold. So I let the mechanic get back to work.
I walked into the service mangers office. He came out to my car we went for drive long story short he agrees it's cold but hands are tied for now but will get advice from higher above.
Called me back and said he has to pull out a 2012 tdi passat he has on his lot to compare to mine. Few hours later he cslls me back to find out his tdi has lots and lots of heat. So next week my is going back in. For what I don't know yet.
 

Rico567

Top Post Dawg
Joined
Jun 13, 2003
Location
Central IL
TDI
2013 Passat TDI SEL Premium (Turned in 7/7/18)
They said they did two flush and said doesnt matter what coolant is used.
So had car checked.
I was told car is doing its job it has enough heat considering the temperature outside That it's the norm with the design of the air box to be cooler on the passenger side.<snip> So next week my is going back in. For what I don't know yet.
This is preposterous on the face of it. DESIGNED to be colder on one side than the other? Nuts. Whoever said that needs to use a little more imagination in coming up with BS excuses.
Last winter we drove from IL to VA, began noticing that "design," passenger side was noticeably cold. My wife was sitting with a heavy blanket over her legs for the rest of the trip. When we returned, heater core was replaced under extended warranty (and I was told everything was flushed), and it's been fine since. "Design," my eyebrows!
 

Bearsvw

Well-known member
Joined
Oct 11, 2016
Location
Orleans ont
TDI
2013 passat highline loaded
I told the service manager after having the heater core replaced last January I had excellent heat but this time it doesn't. Like *** design. When last year it was fine. I told them thst excuse doesn't fly it's not my first winter
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
Springfield, VA
TDI
‘18 Tesla Model 3D+, ‘14 Cadillac ELR, ‘13 Fiat 500e
Pure, unadulturated bullcrap. The HVAC system is not designed to be cooler on one side than the other. When the engine is hot, the heat should be hot - on both sides.

I recommend escalating this issue with VW Customer Care. This is an ongoing problem for more than a handful of people and Volkswagen dealerships need to quit sweeping it under the rug and telling people that it’s functioning as designed.
 
Last edited:

Busydiver

Veteran Member
Joined
Apr 3, 2013
Location
Minneapolis, MN
TDI
Passat TDI SEL
Deadline for turning in TDI's

We did a road trip yesterday starting out in -6F temperatures, heater core that was replaced in the winter of '14 under the extended warranty is still working fine. Let's hope this means it'll hold up until we turn the car in next December.....

When you say your turning in your TDI in December of 2018 is this a lease return or return under the TDI buyback program? ..if it us under the buyback program the deadline for turning in the TDI's is September 1, 2018. if I am wrong please correct me.
 
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