DefinitelyDodgyDave

Hi guys, My 66 Reg 2.0l SE Technology recently developed a low oil/low coolant/oil in the coolant problem. No error messages or high temperature noticed until “check coolant” message appeared on starting one day. Black oil sludge mixed with coolant in expansion tank which was a bit low (tank so opaque can’t see through to judge easily). Also oil was almost down to minimum mark on dip stick. Took to local garage who confirmed oil in expansion tank, explained about bag in expansion tank, mentioned likely oil cooler problem, but couldn’t help anytime soon due to long list of other jobs and staff taking holidays. Suggested local VAG specialist. Local VAG specialist said the most likely problem and cheapest solution (£400) was an oil cooler failure, with the oil (presumably under greater pressure than the coolant) getting through some crack into the coolant. The solution being a new oil cooler, flush out coolant system and replace with new coolant etc. followed by a recommended second flush after about 500 miles. The other possibilities mentioned were cylinder head gasket, and third was cylinder head itself - both were suggested to be probably terminal due to cost of inspection and repair vs residual value of car (180,000 miles). As an aside he also mentioned that once cylinder head taken off and seal broken, new job was never as good as old engine. So had oil cooler replaced (and expansion tank). Since then I have done two 200 mile trips checking regularly en route. First trip showed a slight loss of coolant but no noticeable oil loss. Some black sludge still apparent in coolant when I dipped a wooden splint into expansion tank, but while noticeable was much more like new coolant. So took into the VAG specialist and was topped up and I was told could have been due to an air lock clearing in coolant system. However, after second trip it showed a slight oil loss (2mm on dipstick) but an almost totally empty coolant expansion tank. N.B. No check coolant message. This seems to be a fundamentally different set of symptoms compared to the initial problem where oil loss was much greater and coolant level loss much less (presumably due to oil in coolant forcing coolant out). Also no warning messages at all for coolant or oil. Any hope? Any suggestions? Thanks in advance.