Coolant Loss

[Glasgowsteve]

Not so many. About 45000. I got it when I was doing my old job and a decent bit of travelling then my job changed. 

[varaderoguy]

It can happen. Most Superbs and Octavia's prior to 2017 had duff water pumps that tend to disintegrate prematurely. Stand your car with a cardboard box under the water pump and see what happens....any moisture, it's a new water pump and cambelt.

[Glasgowsteve]

Cool thanks I’ll get that checked out. 

[eacaee]

On 10/10/2021 at 20:49, Glasgowsteve said:

Cool thanks I’ll get that checked out. 

I also have similar symptoms, but now I have to top up after every journey. After investigation I came up with such solutions:

 

- some people had issues with heater matrix clogged causing high pressure of coolant and loosing it through expansion tank - I will check mine heater matrix at weekend (but heating is fine)...

- possible head gasket failure - co2 test on the way, read a few posts about the gasket failure and very similiar symptoms (I think that's the most likely reason for that in my car),

- egr cooler (I doubt it).

[varaderoguy]

It generally either a failed cap to the header tank (they always fail) or the water pump (known issue before 2017 FL cars).  Unless you are filling up your header tank with hard tap water, you won't generally suffer from EGR cooler blockages.  Head Gasket fails do occur, but are rare.  The Heater Matrix is a known issue due to Silica bags splitting and failing (symptoms are lack of heat).

[eacaee]

4 minutes ago, varaderoguy said:

It generally either a failed cap to the header tank (they always fail) or the water pump (known issue before 2017 FL cars).  Unless you are filling up your header tank with hard tap water, you won't generally suffer from EGR cooler blockages.  Head Gasket fails do occur, but are rare.  The Heater Matrix is a known issue due to Silica bags splitting and failing (symptoms are lack of heat).

In mine header tank there's also some black soot and brown residue...

[varaderoguy]

8 minutes ago, eacaee said:

In mine header tank there's also some black soot and brown residue...

oh....that's not good - that's the Silica bag gone south then.  It creates a sludge.  Time to get your coolant system cleaned out and flushed and fresh G12evo put in.

[Zesh64]

I have the same mystery leak.

Mines a 2014 Vrs diesel. 180k miles.

Head tank hold pressure, no exhaust gasses in coolant, spotted a small leak in a hose which was fixed. Replaced the header tank with a new one. No change.

Took it to Skoda who did not want to investigate and even refunded the diagnostic service fee. Most mechanics don't want the headache of investigating as the costs will be large for me and some just said just keep topping it up until you are ready to sell.

Water pump changed with cambelt about a year ago and I've done about 5k miles since then.

I can't see any external drips. I add a UV liquid to coolant and can't see anything glow under UV.

Just had the EGR cooler replaced which made no difference.

 

Car loses coolant faster when under load and have the check coolant warning. Car does not overheat although I have done 10 miles max before eventually refilling G13 coolant.

Economy is a bit worse than before with around 45mpg max on a run. I don't really see white smoke either.

Heaters work fine and no interior leaks.

 

It has a full service history, mostly by Skoda. Nothing noted at last service last month.

 

I can only guess it could be a intercooler leak or thermostat leak but who knows.

 

I also did a stopleak and flush which made no difference.

 

Any advice welcome as I am running out of ideas. I might try waiting to see if temp eventually goes over 90 degrees then refill.

 

 

[SuperbTWM]

8 minutes ago, Zesh64 said:

I have the same mystery leak.

Mines a 2014 Vrs diesel. 180k miles.

Head tank hold pressure, no exhaust gasses in coolant, spotted a small leak in a hose which was fixed. Replaced the header tank with a new one. No change.

Took it to Skoda who did not want to investigate and even refunded the diagnostic service fee. Most mechanics don't want the headache of investigating as the costs will be large for me and some just said just keep topping it up until you are ready to sell.

Water pump changed with cambelt about a year ago and I've done about 5k miles since then.

I can't see any external drips. I add a UV liquid to coolant and can't see anything glow under UV.

Just had the EGR cooler replaced which made no difference.

 

Car loses coolant faster when under load and have the check coolant warning. Car does not overheat although I have done 10 miles max before eventually refilling G13 coolant.

Economy is a bit worse than before with around 45mpg max on a run. I don't really see white smoke either.

Heaters work fine and no interior leaks.

 

It has a full service history, mostly by Skoda. Nothing noted at last service last month.

 

I can only guess it could be a intercooler leak or thermostat leak but who knows.

 

I also did a stopleak and flush which made no difference.

 

Any advice welcome as I am running out of ideas. I might try waiting to see if temp eventually goes over 90 degrees then refill.

 

 

 Charge cooler!

[Zesh64]

2 minutes ago, SuperbTWM said:

 Charge cooler!

Thanks for the succinct response, I actually bought a air charge cooler but will be annoyed if it's replace (like the EGR cooler) then I realise I wasted the cash.

[SuperbTWM]

2 hours ago, Zesh64 said:

Thanks for the succinct response, I actually bought a air charge cooler but will be annoyed if it's replace (like the EGR cooler) then I realise I wasted the cash.

 Quite a few threads on it now on the forum somewhere

 

Others like you have gone to the trouble of replacing the EGR cooler before hand for it not to fix the leak. If you are going to take a punt on these engines I would rather change the much easier to get to charge cooler first. 
 

What you can do is take out one of the temp sensors and have a look in with an inspection camera which you will probably see coolant and/or emulsified oil on the fins of the cooler, especially if you are using a decent amount of coolant

[Zesh64]

7 hours ago, SuperbTWM said:

 Quite a few threads on it now on the forum somewhere

 

Others like you have gone to the trouble of replacing the EGR cooler before hand for it not to fix the leak. If you are going to take a punt on these engines I would rather change the much easier to get to charge cooler first. 
 

What you can do is take out one of the temp sensors and have a look in with an inspection camera which you will probably see coolant and/or emulsified oil on the fins of the cooler, especially if you are using a decent amount of coolant

I have read those threads but some of the symptoms do not quite match mine, I was expecting white smoke which is rarely seen at all. I also do not have rough idling. But you are right, I could ask a mechanic to remove a sensor (I thought it was an air sensor) to look for liquid in the intercooler. 

 

I decided on changing the EGR as most mechanics locally did not want the job and I eventually found one that said yes. There were more willing to do the intercooler so I went for the more difficult and expensive job while I had someone willing to do it.

[SuperbTWM]

If you have had some UV dye put into the cooling system it should be really obvious if the charge cooler is leaking. 
 

I’m not sure if you are aware but there are 2 EGR coolers on these engines so there’s always that as well. 🤣 

 

Merry Christmas 

[Zesh64]

1 hour ago, SuperbTWM said:

If you have had some UV dye put into the cooling system it should be really obvious if the charge cooler is leaking. 
 

I’m not sure if you are aware but there are 2 EGR coolers on these engines so there’s always that as well. 🤣 

 

Merry Christmas 

I hoped that would be the case. 

And I had no idea there were 2 EGR coolers, could you point me to some info on where it is and how the second cooler works?

[SuperbTWM]

46 minutes ago, Zesh64 said:

I hoped that would be the case. 

And I had no idea there were 2 EGR coolers, could you point me to some info on where it is and how the second cooler works?

https://pics.tdiclub.com/data/517/820433_EA288.pdf

 

Pages 50 & 51 show the high & low pressure EGR circuits with their respective coolers.

 

Physical location wise, the low pressure one is the one at the back of the engine, the high pressure EGR cooler I presume is somewhere on the RHS of the engine.

[Zesh64]

On 22/12/2022 at 00:22, SuperbTWM said:

 Quite a few threads on it now on the forum somewhere

 

Others like you have gone to the trouble of replacing the EGR cooler before hand for it not to fix the leak. If you are going to take a punt on these engines I would rather change the much easier to get to charge cooler first. 
 

What you can do is take out one of the temp sensors and have a look in with an inspection camera which you will probably see coolant and/or emulsified oil on the fins of the cooler, especially if you are using a decent amount of coolant

I have just had the air charge cooler replaced and will do a couple hundred miles next week. I will report back if it didn't do the trick. Looking at old cooler, can't see any obviously signs of a leak.

 

Also if it is the low pressure EGR leaking, can't really find that part through a simple Google search.

[SuperbTWM]

3 hours ago, Zesh64 said:

I have just had the air charge cooler replaced and will do a couple hundred miles next week. I will report back if it didn't do the trick. Looking at old cooler, can't see any obviously signs of a leak.

 

Also if it is the low pressure EGR leaking, can't really find that part through a simple Google search.

 

I hope that has sorted it for you, please let us know either way!

[Zesh64]

On 27/12/2022 at 21:17, SuperbTWM said:

 

I hope that has sorted it for you, please let us know either way!

Ok so I did about 70 miles before the coolant warning came on after having replaced the air charge and egr cooler. Really would appreciate so more advise.

 

To recap on other points that makes it difficult to pinpoint the issue.

 

Water pump and timing changed last year.

Reservoir tank and cap holds pressure and shows no exhaust gasses present. Tank and cap replaced recently.

UV indicator in coolant shows no external leaks.

No noticeable white smoke from exhaust.

Coolant was bled after air charge cooler replacement.

Skoda garage could not identify leak and returned car to me.

An independent garage saw no leaks externally.

Coolant loss higher at high load and after about 40 miles plus.

Temp after coolant warning does not go beyond 90, I have driven an extra 20 miles at higher load and it does not move. Normally 1litre needs to be topped up after each warning.

Oil temp stays at 102c - 106c.

No coolant in oil or visa versa.

Heaters working fine on both sides and reach full temp satisfactory.

Radiator Fan turn on with ac.

Performance and idle speed is fine.

Issue has not got any worse over the last year.

No error codes in in diagnostic scans.

 

Is there any condition where coolant is being ejected out the reservoir considering the above?

 

I am stuck with what it could be now.

 

Reading this forum I was off almost certain it was the air charge cooler only. I am now stating to suspect the water pump although it was replaced a year ago. It was done under the previous trade garages ownership period.

 

Open to suggestions that won't involve a big bill to investigate.

 

[SuperbTWM]

If you are are 100% confident that every inch of the engine bay, and the underside has been checked and double checked the only way your car can be losing coolant is by burning it. 
 

Is the car still losing coolant at the same rate? Maybe they didn’t quite get all the air out?
 

 

 

[SuperbTWM]

On 01/01/2023 at 03:28, Zesh64 said:

Ok so I did about 70 miles before the coolant warning came on after having replaced the air charge and egr cooler. Really would appreciate so more advise.

 

To recap on other points that makes it difficult to pinpoint the issue.

 

Water pump and timing changed last year.

Reservoir tank and cap holds pressure and shows no exhaust gasses present. Tank and cap replaced recently.

UV indicator in coolant shows no external leaks.

No noticeable white smoke from exhaust.

Coolant was bled after air charge cooler replacement.

Skoda garage could not identify leak and returned car to me.

An independent garage saw no leaks externally.

Coolant loss higher at high load and after about 40 miles plus.

Temp after coolant warning does not go beyond 90, I have driven an extra 20 miles at higher load and it does not move. Normally 1litre needs to be topped up after each warning.

Oil temp stays at 102c - 106c.

No coolant in oil or visa versa.

Heaters working fine on both sides and reach full temp satisfactory.

Radiator Fan turn on with ac.

Performance and idle speed is fine.

Issue has not got any worse over the last year.

No error codes in in diagnostic scans.

 

Is there any condition where coolant is being ejected out the reservoir considering the above?

 

I am stuck with what it could be now.

 

Reading this forum I was off almost certain it was the air charge cooler only. I am now stating to suspect the water pump although it was replaced a year ago. It was done under the previous trade garages ownership period.

 

Open to suggestions that won't involve a big bill to investigate.

 

Any Progress?

[Zesh64]

On 27/12/2022 at 21:17, SuperbTWM said:

 

I hope that has sorted it for you, please let us know either way!

 

2 hours ago, SuperbTWM said:

Any Progress?

I think I will take this back to the drawing board and take this to a new mechanic with simple task of identifying a leak. For those who don't know here is what others have said:

The RAC - don't know

An independent - a small pinhole leak found and a section of pipe replaced. Not fixed.

Skoda - We don't know, and no charge for the diagnostic fee because we will need to strip the engine.

Another independent - we don't know - sell the car or keep buying coolant. UV dye added and nothing glowing under UV torch.

 

Then based on this forum I changed the air charge cooler and EGR cooler. No change.

 

Any suggestions welcome but next month I will try and have this diagnosed.... again.

[Zesh64]

I have decided to sell the car on as I am having no luck with my local garages not wanting to touch it and/or preparing me for a big bill just to investigate.

Luckily I have made a small profit since owning this VRS for 14 months to the trade. I'll be moving into Audi S4 ownership but this has been a great experience from a community perspective. Thanks to everyone who has offered their opinion for my scenario. Unfortunately my local garages are only looking for quick wins.

[SuperbTWM]

A bit disapointing not to get to the bottom of this but I feel your pain. Maybe the next owner will be along shortly 🤣

 

Hope you enjoy your S4!

[Zesh64]

Thanks, I am sure I will just have different issues in the Audi world but a nice change nevertheless.

I have a working charge air cooler and EGR cooler I need to get rid of, no takers on ebay so will probably bin them soon unless someone wants them. Any offers plus postage cost considered.

[Cactusjack]

The new owner in going to be rather annoyed when they find the issue... Like I was when I purchased mine with your exact problem.

 

Turned out to be a hairline crack in the cylinder head in cylinder no2. Skoda or Indy's couldn't find the issue, even after a head gasket replacement and supposed pressure test, along with egr and charge air cooler replacements by the previous owner...

 

I did a simple sniff test and pressure tested the coolant system when hot and found a slow leak, so I stripped the head out and got a shop to pressure test it individually, I replaced the head with a recon one and the issue magically went away... Bloody hard work though! Quote from Skoda was £4500+ I think to do it for me, I spent around £500 for parts/gaskets/consumables.