oil in sparkplug holes and too much oil pressure

I have a 2001 dodge caravan. After driving it for a couple of hours and turn it off, it will not start. It will turn over, but will not ignite. I took to a mechanic and he checked the fuel pump and filter. These were fine. He told me he found oil in the spark plug holes and there was too much oil pressure. My caravan has 132,000 miles on it. The engine size is a 2.4 liter