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Discussion Starter · #1 ·
Hi guys,

I have done a search before posting, but cannot find anything 100% relevant to my situation.

Anyway I am getting the coolant low light on about once a month. I top the coolant up and then I get the light on again in about a month. I can't see any visible leaks, but maybe there is a slow leak in the system? I think it seems to happen after long journeys when I drive at speeds which are putting a real strain on the engine (120mph) etc.. But I think this just makes me lose water faster... it does need topping up once a month or so anyway (with "normal" driving). My car has also just been serviced and they didn't identify anything! Anyone got any ideas? I'm worried and poor [:(]
 

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If you can't see any leeks, the first place I'd look at is the expansion tank / filler cap for the system. They are designed to also act as a pressure release valve and if they fail, they can slowly but surely realease your coolant...
 

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Discussion Starter · #3 ·
Quote: posted by ct.p on 09/12/2004 00:57:11

If you can't see any leeks, the first place I'd look at is the expansion tank / filler cap for the system. They are designed to also act as a pressure release valve and if they fail, they can slowly but surely realease your coolant...

So do you mean I may need to replace the expansion tank?
 

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Discussion Starter · #5 ·
has anyone else got any suggestions or does everyone agree that it is the cap?
 

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Discussion Starter · #7 ·
ok cheers. How can I test it? take the car for a spin and see if anything leaks out of the cap?
 

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Yes,

Basically go for a run, get up to temperature.

Switch off and listen for a hiss !

Also look around the cap where it meets the header, if coolant is leeking, you'll as more than likely see a residue of dried up coolant there (although probably not to visible with the G12 coolant).

However.....

You may NOT see or hear anything.

Could be all manner of things, but as i've said, the first place i'd look is the cap. I don't think they cost very much for a new one and that would be the best way to be sure.

Other things it can be :-

1, Split hose (residue where leek ocurrs)

2, Faulty heater matrix (sweet smell in cars interior & windows misting up)

3, Radiator punctured (very difficult to spot, but again look for residue)

4, Radiator drain plug not tight (if the golf rad has one ?)

5, Pressure cap as stated above and is the most likely cause.

6, Engine core plug weeping (unlikely but look for residue)

7, Internal leek on oil cooler or inlet manifold (almost impossible to tell without serious dismantling and testing, but very very unlikely)

8, Worse of all, head gasket failure (most expensive, not a DIY fix, but unlikely. tell-tale signs are oil in water and or excessive ammount of white smoke from exhaust even when engine is warm. Also look for what looks like mayonaise inside oil filler cap which is oil & water mixed, can look the same in expansion vessle.)

So there is (i think) a definitive list of what it could be...

Oh .... NEVER take the cap off when the engine is hot without putting a towel over it or similar, coolant can 'leap' out and burn you.
 

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Forgot to mention water pump - its a bearing type where the bearing acts as a seal I believe. Might be on the way out. Mine has just gone! [:(]
 

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when replacing the cap smear the rubber o ring seal with washing up liquid as the seal can ruck up when the caps tightened causeing a coolant loss.
 

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Discussion Starter · #11 ·
Hey guys.... this problem still hasn't been resolved [:(]

Basically my car has been in and out of skoda for the past month now! They have performed serveral pressure tests on the coolant system... Apparently they found a hairline crack in this plastic connector which joins four pipes together? They charged me ?70 for this repair and then to my horror the problem was still present. So it went back and then they claimed it was air in the system. They removed the 'air' and as I thought, that was a load of..... coz the problem was still there! Now apparently they are totally stumped. I suggested the cap which they agreed with. The cap has now been replaced and the problem still exists! I am thinking it is more and more likely to be the head gasket! [:(] I have not noticed any performance difference but my car has the following symptoms:

Lots of white smoke when idling;

A VERY small bit of mayo on the oil cap;

I can often smell petrol while driving!

I am losing coolant (obviously).

A few months back I had a problem with the fans not coming on and my engine temp went up to 130. Reckon this caused the head to warp? My windows steam up too so maybe heater matrix?

Help guys,

Cheers,

Rye
 

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Discussion Starter · #12 ·
Can anyone please help? I need to go to the garage with good advice. This thing is making me really depressed [:(]
 

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It could be the expansion tank itself. I used to get the message saying 'STOP, coolant level low. At first it was occasionally then it started happening regularly. Basically the tank has a sensor in it which quite often goes! The tanks is about a tenner and it certainly solved my problem!
 

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Discussion Starter · #14 ·
Quote: posted by asgh4r on 13/01/2005 10:52:58

It could be the expansion tank itself. I used to get the message saying 'STOP, coolant level low. At first it was occasionally then it started happening regularly. Basically the tank has a sensor in it which quite often goes! The tanks is about a tenner and it certainly solved my problem!

Cheers for help... did yours actually leak coolant or just SAY it was low?
 

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Sorry to say that I too would be concerned about the head gasket given what you've mentioned. Maybe you could ask the garage whether there's anything they can do to make a determination of whether that is the case or not. You obviously don't want to consider a head gasket job unless it's absolutely essential. Are our turbos water cooled? If so, the leak might be somewhere in that vicinity rather than the head.

Finally, with my last car I noticed that if I left it for a week without driving it, when I started up water would come out of the exhaust and the coolant needed topping up now and again. Never found out the cause of the problem but the car continued to run very well with no fall off in performance. All that to say that it may not be something that you have to sort out immediately, annoying though it is.
 

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SOunds to me like a head gasket!

After a long run if you have mayo on the filler cap, you have water in the oil. Your engine could self destruct at any time!!!

Happened to me on my old Polo, the water enetring the cylinders, caused a hydralic effect causing the pistion to stop, timing belt to jump and all bent valves etc.... On a 1.8T this would be disasterous!!

My Polo had been in and out of the VW garage due to a coolant leak for a month before it finally went, I got naf-all out of them, even though they hadn't found the problem!! All I can do is name and shame them at every oportunity, Sloan VW, Edinburgh, useless bunch of cowboys!!!

Oh and BTW, the expansion cap thing is also something they suggested on my POlo, before my engine destroyed itself.

On a golf 1.8T, you should never have to top the coolant up. IF you are there is deffo a leak somewhere!

Good luck, my advice is get it sorted sooner rather than later!
 

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Best way to check this is to get the garage to pressure test your cooling system.

Basically, they pump the system up to (and beyond) working pressure, and check to see if the pressure drops. If it does, you have a leak, and can then look to see where it is without getting scalded.

Should only take an hour with the right kit.

If there are no visible signs of leakage, then you can start to worry about head gaskets, water pumps and suchlike...
 
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