I recently replaced the plugs on my '95 Trooper 3.2L, SOHC (~100K miles) in reponse to some sluggish performance. In doing so, I found two of the plugs immersed in oil. In addition, the valve cover has needed replacement for a couple of months - I've been noticing leakage.

In doing a little research, I've found that it is not uncommon for the spark plug seals to leak on the pre-98 3.2L engines. Given the vehicle is >10 years old, and ~100K miles, this isn't a surprise.

I've replaced valve cover gaskets and spark plug seals before, but the confiuration of the fuel injection, etc. on the Trooper worries me - I know enough to be dangerous, but I think this one's a bit over my head.

How much should I expect to pay at a dealership for the gasket & seal work?

Thanks!