On both of these trucks, the valve cover nuts (at the lower edge) were finger tight, or backed off a full turn from being tight. Neither had been touched since they left the factory, as far as we knew. My buddy's Taco was leaking oil badly down the pass. side of the block, and my 4Runner was just starting to.
So, check the lower-edge valve cover bolts on both sides of your 3.4. When I saw how loose they were, I was surprised.
So, check the lower-edge valve cover bolts on both sides of your 3.4. When I saw how loose they were, I was surprised.