Why is there oil in all 8 of my cylinder heads?

Hello, are you saying that you have oil on your spark plugs in the cylinders? Or are you saying that there is oil under the coils? Where are you finding the oil? https://repairpal.com/repair-shops/audi-repair-and-service-in-wakefield-massachusetts

Valve cover gaskets have deteriorated - replacement required. The gasket SET includes new spark plug tube seals - that’s what’s allowing oil to pond around the spark plugs - as seen when the ignition coils are removed. Oil ponding around the spark plugs ‘WILL’ result in engine misfires.