Coolant loss with a big history of problems

[Davehasaskoda]

Right where do I start...my cars a Octavia 1.9tdi 115k miles.

I need help to find why my car is losing coolant.

It loses about a litre overnight, and can't even drive 40 miles without the warning lights flashing on. Its been in the garage they pressure tested it and replaced the tank and cap. Problem still not fixed, then bypassed the egr cooler and still leaks so guess its not that either.

History the car had a new cylinder head, valves, water pump, etc after a cambelt failure only 6 months ago.

The car was fine for months until I had fuelling problems which after spending a lot of money at Skoda dealer and local garage turns out to be fuel pump thats'on its way out.' Which I haven't replaced yet. The coolant problem only started after it went be fixed for fuel problems!

I know this is a lot to read but please if anyone has any helpful information or previous experience with similar problem.

[bigjohn]

1) Radiators can be prone to failure - not always obvious as water tracks down the outer edge of the rad and then onto undertray. 

2) Heater Matrix inside the car can fail as well

3) Worth double checking new water pump as well although these tend to leak in use and not overnight if faulty

Edited 16 November, 2015 by bigjohn

[Davehasaskoda]

Thanks for the reply,

Dont think it's the radiator.

My mechanic only changed the water pump with the new cylinder head and cambelt etc...so he claims that it can't be that (probably because he would have to do it under warranty if he did.

I had a thought that it could be the heater matrix too, bt im unsure. I will see if this can be by-passed and check for further coolant loss.

[blackspaven]

If it's the matrix which'll leave water inside your car, stick the extension attachment of your hoover straight onto the carpet and see if you get bubbles when you take it away. Sounds odd, and you don't have the problem I had, but I found out I had water ingress when hoovering the car this way. Never did find the cause, but after the bubbles, I subsequently took the door trim up a little and looked under the carpet & stuck my fingers in there, it was sodden, but I was oblivious to it before I accidentally ran the full suction over the carpet which drew some through it: the padding under there is bloody absorbent!!

 

MkII golfs had a recall for leaking matrices and it can go unseen with so much padding, although like the golfs, you'd be getting a lot of condensation if it was that.