I changed the plugs on a recently bought 2007 Honda Odyssey with the 3.5 liter engine. This van has 249,000 miles and a substantial oil leak from the firewall side of the engine. The middle plug in the back had quite a bit of oil on the porcelain. The plug on the back driver side had a little oil on the porcelain. The middle plug in the front has some brown rusty paste looking stuff, I don't know what it is. Front plugs on the right of the picture, back plugs on the left.
How does this oil get into the spark plug tube?
How does this oil get into the spark plug tube?