white residue under cap


Registered User
I've just found some of the old milky white residue under my oil cap, its also in the pipes coming off the top of the engine. Has anyone else had this problem and its not turned out to be the dreaded head gasket? if head gasket is the way its going whats an approx price?



Registered User
Not cheap if it is the head gasket. Have you been doing lots of short journeys recently though? I would clean the cap then take it on a long journey an see what happens.


***** rent boy
VCDS Map User
People need to say what engines they have before they describe their symptoms.

It's not always the head gasket, in the 1.8T the oil cooler can become faulty and the coolant and oil will mix making it appear as though the head gasket is leaking when it's not. Also if you only drove a short journey and the coolant reads 90c the oil will only be partially warm, oil takes a little longer to reach operating temperature, and this could be the cause of the milky substance.


Registered User
sorry, its a 1.8T AVJ engine. I pop out in it for 1/2 hour tomorrow to and see what happens. I have only been on short journeys recently so hopefully its this.



Registered User
You might want to try a combustion leak test.

If the combustion gases are passing over the gasket this tool detects the gases present. Another way is to see if you getting excessive white smoke (steam) from the exhaust along with a coolant level drop.
Another way is to check if the coolant hoses to the radiator seem to have excessive pressure due to high pressure gases leaking into the coolant system
a further way to chck for head gasket failure is retained pressure in the expansion tank. retained pressure in radiator hoses, and also if its really bad, if you rev the car with the cap off the expasion tank, the water will bubble!