Oil around injectors not diesel Volvo C30 2008
 

On further investigation of the oil leak, and having replaced the rocker cover gasket the oil is popping around one particular injector. This is definitely oil not diesel. I was wondering if the injector gasket was leaking? Would there be a possibility of oil leaking up through the gasket? Is there an oil gallery below it, or does it go directly in to the combustion chamber ? I’m probably getting about a teaspoon of oil after 10 minute drive. Thanks