My car is a 2007 Octavia Scout.  It is running beautifully, but few weeks ago I noticed dirty engine oil in the coolant header tank.  "Ooh, blown head gasket, very expensive", said several people, but a bit of research on Briskoda, and a conversation with a local independent VAG specialist, suggested a 75% chance that it was the oil cooler: a lot less expensive.  I got my trusted garage (not the VAG one) to change the oil cooler (£235 including labour and VAT) and I am cautiously - very cautiously - optimistic that it has worked.  There is still oil in the header tank but it is a very thin skim which I assume arises from residual oil in the engine coolant galleries.  I don't think my garage flushed the system before they refilled it, which would have been useful.  I plan to get that done soon.

 

However, my question is about something they said.  They had previously told me that if the oil cooler change didn't work they would walk away from it, because they have tried changing head gaskets on these cars before, and it has never worked.  The independent VAG person said this is because the gaskets on these engines don't blow unless there is something else more fundamentally wrong: typically a warped head, which would require skimming.  "Nonsense", said my garage, "it would mean that the original problem with oil leaking into the coolant was caused by porosity in the head".

 

Can it really be true that a 14-year-old engine, with less than 90,000 miles, could suffer from porosity?  I've got a 1928 vintage car which has suffered from engine porosity in alloy parts, but the problem arose in an original part which was over 80 years old at the time!

 

What do the experts here think?  (By the way, I will update in a few weeks when I have driven the car some more and had the coolant system cleaned out.)

 

Thanks!

31 minutes ago, scandalxk said:

Can it really be true that a 14-year-old engine, with less than 90,000 miles, could suffer from porosity?

Yes, but if it does then there's a fundamental QC problem at the foundry.