[NoVa-Corvairs] non-Corvair tech question

[Daniel Goldberg]

My 1990 Bronco II (159k, 2.9L V6) is losing power and consuming a great deal of gas.  I wanted to perform a compression test, but my tester would not fit into the plug holes.  Nevertheless, removing the spark plugs revealed that two (#1 and #5) were quite oily.

Oily plugs are usually indicative of bad rings or bad valve seals, no?  Is there a simpler (i.e., non-internal) explanation for the symptoms I described, or should I rid myself of this beast?

goldie.