Really? The platinum 4's aren't recommended for this engine? Thats surprising.... why not? Guess I made a mistake there.
Still, it was revving before I replaced the plugs, so I doubt that is the source of the problem. I'm still curious about my original question... does the throttle actuator go bad on these engines? Most of the post's I've read look like suginami's.... "I replaced the throttle acutator and it didn't change anything. Then I replaced XXX and it fixed it.