Disappearing coolant!

Turbo Girl

Member
Joined
May 24, 2012
Location
Bloomington
TDI
2006 Jetta TDI/5 speed
PLEASE help me! I have an 06 Volkswagen Jetta TDI 1.9L engine 5M. My car is losing coolant and I have NO idea where its going. I am not very vehicle savvy and I have no idea what to do. Last winter and this winter I have been having the same problem: when I accelerate rapidly or am going up a hill the vehicle begins shaking and "sputtering" and will not accelerate or acceleration will increase very slowly. I assumed I had an intake problem and planned on taking it to the repair shop after the holidays. Well on my way to visiting my family the problem signifcantly escalated. I was not able to drive over 60 MPG on the highway without losing all acceleration and now I am losing coolant. I do not see a leak, it is not on the ground under my car or on the belly pan, and the tank is bone dry. I can fill the tank to the max line and drive it for one day and by the time I go to start the vehicle the next morning the tank is completely empty. What is going on??? It only happens in the winter. Over the summer I did not have this problem.
 

Tdijarhead

Top Post Dawg
Joined
Nov 10, 2013
Location
Lawrenceville PA
TDI
2003 TDI Jetta Daughters Car, 2001 TDI Beetle, Wife’s car, 2005 Golf TDI Mine, all 5 spds
Take the oil filler cap off, is there any milky sludgy crap on it? Pull the dip stick where is the oil level? Is there any milky sludge on the dipstick?
 

Turbo Girl

Member
Joined
May 24, 2012
Location
Bloomington
TDI
2006 Jetta TDI/5 speed
Take the oil filler cap off, is there any milky sludgy crap on it? Pull the dip stick where is the oil level? Is there any milky sludge on the dipstick?
I have not had the chance to look at the oil filler cap because I am at work but the oil level is fine. I guess its milky. Definitely "burnt" though. I am in need of an oil change. I just hit 4,000 miles in the car since my last oil change.
 

Tdijarhead

Top Post Dawg
Joined
Nov 10, 2013
Location
Lawrenceville PA
TDI
2003 TDI Jetta Daughters Car, 2001 TDI Beetle, Wife’s car, 2005 Golf TDI Mine, all 5 spds
The recomended oil change interval for you car is 10000 miles provided of course you used the correct oil. If your oil is milky/whiteish colored then I believe you have found your coolant leak. You need to double check for sure but milky colored oil indicates a lot of coolant has mixed with your oil. A small amount of that milky colored sludge crap on your oil filler cap indicates the beginning of a problem, although during the winter sometimes it's just a little condensation. Is the oil level on your dipstick above the add mark? And is the
oil itself that is on the end of the dipstick actually milky colored? Or muddy light colored looking?

It's important to be precise about the color, brown/brownish, amber is more or less normal. Any white streaks or whiteish color is not what you really want to see.

Define "burnt". Smell?
 

Turbo Girl

Member
Joined
May 24, 2012
Location
Bloomington
TDI
2006 Jetta TDI/5 speed
The recomended oil change interval for you car is 10000 miles provided of course you used the correct oil. If your oil is milky/whiteish colored then I believe you have found your coolant leak. You need to double check for sure but milky colored oil indicates a lot of coolant has mixed with your oil. A small amount of that milky colored sludge crap on your oil filler cap indicates the beginning of a problem, although during the winter sometimes it's just a little condensation. Is the oil level on your dipstick above the add mark? And is the
oil itself that is on the end of the dipstick actually milky colored? Or muddy light colored looking?

It's important to be precise about the color, brown/brownish, amber is more or less normal. Any white streaks or whiteish color is not what you really want to see.

Define "burnt". Smell?
Maybe I didn't understand what you mean by milky. Its not whitish. The oil is burnt black. It shouldn't be like that since I just changed it and as you stated, it should last me 10,000 miles. When I use the word burnt, I mean black and charred looking. I have not smelled it.
 

Tdijarhead

Top Post Dawg
Joined
Nov 10, 2013
Location
Lawrenceville PA
TDI
2003 TDI Jetta Daughters Car, 2001 TDI Beetle, Wife’s car, 2005 Golf TDI Mine, all 5 spds
Maybe I didn't understand what you mean by milky. Its not whitish. The oil is burnt black. It shouldn't be like that since I just changed it and as you stated, it should last me 10,000 miles. When I use the word burnt, I mean black and charred looking. I have not smelled it.

That's just normal diesel oil. Looks like its been in the engine for 100000 miles. Brown/amber colored when you put it in, black shortly thereafter.

No white milky coloring or sludge is a good thing. Another possibility is the water pump may be leaking. Although I would think that with as much coolant as you're describing even a leak there would show up on the dust sheild. To check the water pump you will have to pull the upper part of the timing belt cover and look with a flashlight down inside the lower cover for wetness.

Do you notice any sweet smell after your engine gets hot and you pop the hood?
Antifreeze has a "sweet" smell if it gets hot and burns off an exhaust manifold for instance.

Is there any wetness anywhere on or around your radiator? Maybe a wet spot on the ground up near the front of your car? Can you smell that "sweet" smell?

How about an unusual smell inside the cabin? Are the carpets in the front where you put your feet wet? From other than snow or rain tracked in?
 

sdeck

Veteran Member
Joined
Aug 25, 2006
Location
Northern Colorado Front Range
TDI
2003 Jetta, 253K, 01M, DLC520s, VNT-17(sold); 2014 Passat SE 6M, 61,000 miles (Feb 16 buyback date)
Black oil is normal in these engines even immediately after an oil change. Not burnt. It's soot from combustion. Perfectly normal. The oil in these engines is designed to handle it, provided you are using the correct oil.

What jarhead is worried about is coolant getting into oil from leaking head gasket. That's bad. Usually shows up as milky brown oil or "mayo" like crud on the inside of the oil fill cap. If you have none of these, then it's leaking somewhere else. Probably external. How much are you losing?
 

turbocharged798

Veteran Member
Joined
May 21, 2009
Location
Ellenville, NY
TDI
99.5 black ALH Jetta;09 Gasser Jetta
It could be several different thing that can cause loss of coolant. Most common on TDIs are EGR coolers, radiators rotting at the bottom, and headgaskets.

It could be a headgasket and the only way to test for this is to hook up a pressure gauge to the cooling system and watch for quick rises in pressure. This would probably be my first line of action just to rule out the biggest issue. Doing a pressure test is quick and easy.
 

turbocharged798

Veteran Member
Joined
May 21, 2009
Location
Ellenville, NY
TDI
99.5 black ALH Jetta;09 Gasser Jetta
Black oil is normal in these engines even immediately after an oil change. Not burnt. It's soot from combustion. Perfectly normal. The oil in these engines is designed to handle it, provided you are using the correct oil.

What jarhead is worried about is coolant getting into oil from leaking head gasket. That's bad. Usually shows up as milky brown oil or "mayo" like crud on the inside of the oil fill cap. If you have none of these, then it's leaking somewhere else. Probably external. How much are you losing?
TDIs almost never put oil in the coolant during a bad HG. The only way to do the pressure test I mentioned above.
 

Tdijarhead

Top Post Dawg
Joined
Nov 10, 2013
Location
Lawrenceville PA
TDI
2003 TDI Jetta Daughters Car, 2001 TDI Beetle, Wife’s car, 2005 Golf TDI Mine, all 5 spds

sdeck

Veteran Member
Joined
Aug 25, 2006
Location
Northern Colorado Front Range
TDI
2003 Jetta, 253K, 01M, DLC520s, VNT-17(sold); 2014 Passat SE 6M, 61,000 miles (Feb 16 buyback date)
Good point turbo.

Regarding the OPs other acceleration issue, they may or may not be related. It sounds like she needs to get it looked at by someone who is "vehicle savvy". There is a TDI guru list at the top of the 101 forum page. Find someone close. Do Not take it to a dealer or any shop that doesn't specialize in these engines. Way too much risk of wrong diagnosis.
 

Turbo Girl

Member
Joined
May 24, 2012
Location
Bloomington
TDI
2006 Jetta TDI/5 speed
I'll check this out...I just replaced the clutch, timing belt, alternator, temperature "reader", serpentine belt, water pump, and some bracket that holds one of the belts on. I didn't start having this problems until after I replaced the alternator, serpentine belt and temp thing. The alternator "crumbled" according to my repair guy and it broke the belt. I am not sure why they also replaced the temp thing.


I feel like my oil was JUST done. I have driven 4,000 miles since I replaced it last so its been in the engine for only 4,000 miles and not 10,000. Should I be concerned about that?


I'm not smelling anything sweet when this happens and I pop the hood. When it happens and I pull over to check things everything seems fine. No wetness. I am going to have to look harder tho.
 

VeeDubTDI

Wanderluster, Traveler, TDIClub Enthusiast
Joined
Jul 2, 2000
Location
La Conner, WA
TDI
2018 Tesla Model 3: 217,000 miles
TDIs almost never put oil in the coolant during a bad HG. The only way to do the pressure test I mentioned above.
Yeah I've never seen a diesel put coolant into the oil. In my experience, it has always been combustion gas into the coolant, which overpressurizes the system and causes it to barf out of the pressure relief cap.

Take the car for a good 20 minute run on the highway and get it up to operating temperature. Bring it back home and park it. After three hours, squeeze the coolant hoses and see if they're hard. Then, pop the coolant cap and see if it releases a lot of pressure. If the hoses are hard and it releases a lot of pressure, then you have a blown head gasket - textbook symptoms.
 
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