Jetta MK4 TDI Loosing Coolant

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Papa TDI
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Jetta MK4 TDI Loosing Coolant

Post by Papa TDI »

Hi All

I'm the proud owner of a Jetta MK4 1.9 TDI she's siting @ 483535 kms i've noticed lately she's loosing coolant like nobody's business and it started at abt a lt of water per week however it became worse over time when between my work commutes(Crystal Park-Marshalltown-Parktown & back) i have to top up. I've even stopped using anti reeze as it's just a waste with the regular topping up, so long story short i've replaced the oil cooler(Goldwagen East Rand) on Friday and did minimal kilos over the weekend and it did'nt loose water however i've just checked it now at work there's no difference water gone! Before i changed the Oil Cooler there was a little bit of oily mix in the coolant resevoir so i had it cleaned & changed the Oil Cooler so the water is now rusty brown resembling dirt and surprisingly there's no water in the oil & on the carpets as suggested by my neighbour & visible leakage of water in the engine compartment etc so i'm out options.

Any advice will be greatly appriciated.

Regards
Callum229
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Car Model: Jetta MK5 TDI DSG Highline
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Re: Jetta MK4 TDI Loosing Coolant

Post by Callum229 »

Rusty water is corrosion.

Are you getting a constant stream of water on your return line(small pipe that goes to the coolant bottle)?

Did you check your coolant bottle for any signs of leaking or overflowing?

Does your heater work constantly in the car when you put it on heat?

Does your car ever go over 90 degrees or overheat?

FIrst you have to flush the coolant out until its sparkling clean and take it from there. inspect the piping on the side of the head, under the tandem/vacuum pump as it can leak and evaporate from there.
2007 VW Jetta MK5 1.9 TDI DSG,

Mods: Simple EGR delete, LED interior set up, LED rear footwell lights, LED Puddle lamps, LED Doorhandle illumination, LED License plate lights, LED Boot lighting.

2007 VW Golf 5 1.9 TDI DSG, no mods.

2007 VW Transporter 2.5 TDI 4motion, no mods.
Papa TDI
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Re: Jetta MK4 TDI Loosing Coolant

Post by Papa TDI »

Hi Callum

Thanx for your responce, will definetly focus on the below & revert.

>Are you getting a constant stream of water on your return line(small pipe that goes to the coolant bottle)?
>Did you check your coolant bottle for any signs of leaking or overflowing?
>FIrst you have to flush the coolant out until its sparkling clean and take it from there. inspect the piping on the side of the head, under the tandem/vacuum pump as it can leak and evaporate from there.

As the car does'nt overheat or go over 90* & the heater is working pefectly fine on heat.

Regards
Callum229
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Posts: 251
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Car Make: VW
Car Model: Jetta MK5 TDI DSG Highline
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Re: Jetta MK4 TDI Loosing Coolant

Post by Callum229 »

Also, try and use a dye in your coolant to check where it is leaking, some leaks can be a pain to find.
2007 VW Jetta MK5 1.9 TDI DSG,

Mods: Simple EGR delete, LED interior set up, LED rear footwell lights, LED Puddle lamps, LED Doorhandle illumination, LED License plate lights, LED Boot lighting.

2007 VW Golf 5 1.9 TDI DSG, no mods.

2007 VW Transporter 2.5 TDI 4motion, no mods.
Papa TDI
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Re: Jetta MK4 TDI Loosing Coolant

Post by Papa TDI »

Hi All

Since my last post regarding the loss of coolant, i've done some DIY i.e cleaned the cooling system, changed the coolant bottle & cap however i can confidently say that nothing has changed what i have noticed is the water is ofbrownish/rusty colour also during my commute to work it drves nicely however afternoon i have to stop & top up as it signals on the cluster what's also puzzling is the hissing sound n the morning when i check the water level cause the coolant bottle is so dirty can'teven see where the water level is.

Am I in for a blown head gasket or worse?

Regards
Callum229
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Posts: 251
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Car Model: Jetta MK5 TDI DSG Highline
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Re: Jetta MK4 TDI Loosing Coolant

Post by Callum229 »

Have you checked if the water is coming out from your cap? if the cap is faulty or there is excessive pressure in the cooling system, it will empty there. When I had a head gasket issue, the coolant would exit on the side of the bottle and evaporate/hide on the side of the fender, which makes it harder to see as when you looking for a coolant leak, you usually look at the radiator and engine.

Run a couple of bottles of radiator/coolant flush and maybe take out the bottle and scrub it. Attach a sponge to a strong piece of wire and scrub the inside and also scrub the outside with some engine degreaser. Rinse and make sure it is clean.

if the water is dirty, it could be just struggling to move the water and heating up.

Check the following.
- There is a thin coolant pipe on the head, by the tandem pump, check that it isn't blocked, and check the nipple on the head as well. You can poke a piece of wire and check that it is clear with no dirt.
- Reverse flow the radiator with the pipes disconnected, to dislodge all the dirt and rust.
- Did you check if the small pipe to the coolant bottle is flowing water? It must flow a steady stream of coolant.
- Check when the engine is running, there should be no bubbles coming out the bottom of the bottle, that is one of the signs of a blown head gasket.
- Your heater will go hot and cold when on full hot and you are driving on the freeway, this is also a sign of a blown head gasket.
- Remove thermostat and run without the thermostat and check. You can also check if your waterpump blades have gone loose, you can put your hand inside where the hole for the thermostat is and feel for the fins and try and move them.
- You can go to a shop and ask them to check for head gasket failure, they will use a tester that checks for exhaust smoke in the coolant, this isn't accurate though, so use it as a last resort.
2007 VW Jetta MK5 1.9 TDI DSG,

Mods: Simple EGR delete, LED interior set up, LED rear footwell lights, LED Puddle lamps, LED Doorhandle illumination, LED License plate lights, LED Boot lighting.

2007 VW Golf 5 1.9 TDI DSG, no mods.

2007 VW Transporter 2.5 TDI 4motion, no mods.
Papa TDI
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Registered for: 6 years 8 months

Re: Jetta MK4 TDI Loosing Coolant

Post by Papa TDI »

Hi Callum

Thanx very much for your responce, In conclusion to this is that i have a blown head gasket on weekend i ordered a new coolant bottle from VW Benoni it was fitted yesterday & i've checked this moning water gone again brownish/rusty colour as usuall the new bottle looks like it's from 5 yrs ago, i've literally exhausted all avenues will engage a mechanic and report back.
Callum229
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Posts: 251
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Car Make: VW
Car Model: Jetta MK5 TDI DSG Highline
Location: Durban
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Re: Jetta MK4 TDI Loosing Coolant

Post by Callum229 »

If it is badly corroded, just a firm warning, you might need a new head or aluminum welding on the head.

Remember though, the aluminum welding is expensive and might not be strong enough.

Also, if it has been flushed properly, it should be clean or near clean. Make sure the mech flushes the system throughly and then evaluate.

It could also be failed oil cooler and it might be leaking oil into the coolant?
2007 VW Jetta MK5 1.9 TDI DSG,

Mods: Simple EGR delete, LED interior set up, LED rear footwell lights, LED Puddle lamps, LED Doorhandle illumination, LED License plate lights, LED Boot lighting.

2007 VW Golf 5 1.9 TDI DSG, no mods.

2007 VW Transporter 2.5 TDI 4motion, no mods.
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Re: Jetta MK4 TDI Loosing Coolant

Post by Tdi jetta 4 ever »

Might be the water pump leaking or radiator otherwise its your head gasket.
Robin
Current rides: 02' Jetta 4 1.9 Tdi, 99' Isuzu KB 250 Dle(Faithfull aka slowmo) Mercedes Benz ML 270Cdi
Ex rides: 82' jetta 1.5 Gls(sold), 88' jetta Clx(sold with tears in my eyes)

Rather buy a good quality part that will last then buying a cheap part that won't last.


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VAG Fan
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Re: Jetta MK4 TDI Loosing Coolant

Post by VAG Fan »

Interested fellow Mk4 TDI driver, would like to hear what the problem was.
Subscribed.
Mark R.
- - - - - - - - - -
2004 VW Golf TDI, type 1J, AHF, 317k (2016-current) --- daily
1990 VW Fox, type 16, HM, 304k (2005-current) --- spare runaround
Previous:
1992 Audi 500 SE, type C4, AAR (2001-2020) --- nice while it lasted
1983 VW Golf GTS, type 17, FR (1992-2005) --- most fun car I've ever had
1978 Audi 100 GLS 5E, type 43, WC (1991-92) --- died in the side of a Rekord who cut me off
- - - - - - - - - -
Papa TDI
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Re: Jetta MK4 TDI Loosing Coolant

Post by Papa TDI »

Hi All

Sorry for the late response, however just a heads up & much appreciation to all advises received, turns out i had a blown head gasket had it replaced(Victor Reinz Alert Engine Parts Boksburg)), cleaned cooling system, new water bottle & VW G12 coolant now she's purring now did two round trips to Seshego in Limpopo for a funeral no worries.

Regards
VAG Fan
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Re: Jetta MK4 TDI Loosing Coolant

Post by VAG Fan »

Thanks for the feedback, much appreciated.
I suppose half a million km is not bad for any engine or gasket. (Mine is only at 280k, but just as old...)
Mark R.
- - - - - - - - - -
2004 VW Golf TDI, type 1J, AHF, 317k (2016-current) --- daily
1990 VW Fox, type 16, HM, 304k (2005-current) --- spare runaround
Previous:
1992 Audi 500 SE, type C4, AAR (2001-2020) --- nice while it lasted
1983 VW Golf GTS, type 17, FR (1992-2005) --- most fun car I've ever had
1978 Audi 100 GLS 5E, type 43, WC (1991-92) --- died in the side of a Rekord who cut me off
- - - - - - - - - -
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