Oil in coolant but no coolant in oil. Combustion gas in coolant test showed present gases. With the gases in coolant can it still just be oil cooler?

[mikeote]

Heya, thanks for looking at my thread.

My sisters MK4 golf has oil in coolant but no coolant in oil. Combustion gas in coolant test showed present combustion gases. With the gases in the coolant can it still just be the oil cooler? Or is it now definitely either: head gasket or cracked head or leaking exhaust manifold gasket?

Cheers!
Mike

[Crasher]

It would be nice to know which engine it had?

[mikeote]

Heya Crasher,

Oh yeah it would... It's a TDI but I'm not sure what the engine code is.

Cheers!
Mike

[Crasher]

If it is a 115, 130 or 150 PDTDI, these are prone to head gasket failure, especially the 115PS.

[mikeote]

Thanks for that, can I rule out oil cooler considering there's combustion gases in coolant?

Also can you let me know how you'd find out if it is the exhaust manifold gasket leaking instead of the head gasket?

Cheers

[Crasher]

To see oil in the coolant from a head gasket leak is very rare, I simply cannot remember the last one. To misdiagnose combustion gases in the coolant using the usual chemical dye kit from Snap Off is common, I sometimes think it would say there are combustion gases in fresh water and the VAG coolant bottle seems to make it impossible to take a good sample without pulling coolant in which gives the same result as combustion gases. The PD TDI only tends to show head gasket issues under load such as on the motorway and it blows all the coolant out, oil coolers fail all the time.

[mikeote]

Thanks for the brilliant reply Crasher, even when you think you've done the sensible thing testing; it turns out that you can't be sure even then. Some times it seems like practicing voodoo is more of a certain art. I'll pass the info on to my sister and recommend we just go ahead with the oil cooler replacement / full coolant flush and see how she goes.