Morning all. 

I know its a recurring topic with the mk3 octivia's. Had mine up at the dealers for its service. Picked up a coolant loss. Stopped by the garage I use. They had a look includeing putting 2 bar of pressure on the coolant system. They cant get the car to leak, but the car is using coolant. It has a leak but I cant find it. Nor can my garage.
The car tempture guage holds steady.
Any one got any idears, thoughts ect??

Its had the cam belt and pump changed last year. Its not leaking from the pump, nor where the thermerstat is!

Help!!

Edited 20 February, 20197 yr by Stuart-h

I have been three Car with 2.0TSI engine.2014 RS TSI, 2016 LEON CUPRA and 2018 TSI RS.all car has little coolant loss.Two first car dealers do the pressure test, but everything was ok.

So i put little more coolant time to time and hard driving..

Mine too had a slight leak and I'm hoping it's the water pump as it's due a cambelt and pump in the next few months.  I've never seen any trace of coolant loss but I do occasionally get a smell of coolant round the front of the car after a long journey.

 

You could try adding a dye to the coolant and see if it's visible under uv light, I brought some but never got round to doing the test yet.

Cheers scout. Where do you get the dye from?

Something like this?

 

https://www.amazon.co.uk/Torch-Detection-Cooling-Antifreeze-System/dp/B00TU8VCB4

I used that on my MG to trace a leaky hose. It worked very well and found the problem. Fixed it and it never came back. But for best results, you do need to examine the engine bay and under the car in complete darkness - unless it's a really obvious leak.

 

And then the torch comes in useful for checking the cleanliness of the next cheap hotel you stay in

Cheers guys  

least it’ll save the cost at the dealers! 

I'd wager that it is a slight leak from where the radiator core joins the sides.

I’m beginning to think that as well Gti. I can’t see any marks there though ! 

I have also the same problem, the light came on today again and when I opened the bonnet, around the filler cap was damp and also the small bit of metal right under the coolant tank was wet.

 

Could the there be a fault with the cap and it's lifting under pressure and losing the fluid that way? The bottle was nearly empty

Had a similar issue on my old car. Replaced the 2 seals on the pipes going into the front of the engine from the coolant. Cost about £6 and now all is good. 

18 hours ago, Steveyboy said:

I have also the same problem, the light came on today again and when I opened the bonnet, around the filler cap was damp and also the small bit of metal right under the coolant tank was wet.

 

Could the there be a fault with the cap and it's lifting under pressure and losing the fluid that way? The bottle was nearly empty

Possible. Ive swaped the cap from the fabia onto mine. Just the small matter of getting a decent few long haul runs.