head gasket
It is common for these 12 valves to start a leak near no 1 cyl, seepage is more like it. Mine did at about 500k, pulled head to repalce gasket as a precautionary measure, new head gasket , no issues with the innards and repalced the head and now with about 950,000 miles still going strong .
don't let the dealers scare you. stormy