HI All

any advice appreciated ! 2 and half years ago had head gasket done (80000 mile) due to coolant p!22ing through expansion tank relief valve.This cured the problem and was advised it was combustion gases entering the coolant circuit at high load pressurising the coolant. I had 12 months trouble free motoring then had a very nice but slightly reduced shark remap done. Transformed the car, absolutely the best money i ever spent !!

Now, Im trying to keep this not too long so....before head gasket change symtoms were, LOSS OF COOLANT, WARNING LIGHT ON DASH. COOLANT ESCAPING FROM HEADER TANK RELIEF VALVE IN HUGE AMOUNTS AFETR HARD DRIVE, MASSIVE PRESSURE AFTER SHORT JOURNEY IN PIPES....

Now to present days, I have what is the same consistancy as beer foam in top of expansion tank after a drive. It isnt oily, yellowy coloured it is like soap suds,pure white. You scoop it into your hand and all bubbles pop/dissipate, disappear in seconds. I was also loosing coolant initially from min to max mark over 300 ish miles but now the really cold air is here its every 100 ish miles. I've put paper roll around exp tank and leathered the car but cannot replicate the symptoms before head gasket had gone. All i get is a little water vapour around the header tank exit but THE COOLANT IN THE EXPANSION TANK IS NOT RAISED ??. My question is , is it possible for there to be some addative left in the coolant system that would cause the foaming and allow pressure /condensed liquid out of the relief valve or am i staring down the barrell of another head / head gasket problem ?. No starting issues, car runs a dream and i dont want to trade her in to another poor soul !!

thanks , chris

Is there any evidence of coolant in the oil? This may give you more of an idea. Only other way to positively rule out headgasket is to get a garage to perform a leak down test. No matter what coolant was used, 12 months should be nothing for it. I'd be very much surprised if it was as simple as a fluid issue I'm afraid.

Maybe its worth draining off all the coolant, flushing and refilling with known good stuff. The car should have G12 or G12+ in it, which are a pinkish colour. Mixing this with any other type of antifreeze can cause weird chemical reactions which will ultimately lead to things clogging up.

thanks for replies. Should have added that i did a full coolant change (G12+ from VW ) and also dropped and flushed twice the old stuff before adding the new. There's no water in the oil (mayo) and no visible oil in the coolant, just piles of foam in header tank. Im starting to think theres been a cleaner of some sort that has for whatever reason come back to life after the change last year ? weird....Anyways i'll put it in for a sniff test and pressure test next week to get the ball rolling.