My recently acquired MY02 WRX wagon has a very slight (but messy) oil leak. Slow enough that overnight in the garage it doesn't actually leave a drop on the floor, but it is clearly a mess underneath. Both valve cover gaskets look messy, I plan to replace those, but I'm wondering if this mess around the oil filter is a different leak? It appears to be coming from above the filter, are there any common leaks in here to look for before I tear it apart?
Thanks.