The poor Pathfinder got a little too deep, once again and subsequently bogged out in some muddy water. I winched it out and gave it a turn with the starter and it did about a half rotation before stopping. Pulled the coil packs, plugs, and cleaned the wet ones up, turned the engine over and put the plugs back in. It fired up and ran fine after a couple of tries. I checked the oil and there seemed to be no water in it, and the level hadn't chaged. After an hour or so heading it developed a slight knock around 3500 rpm at which point i checked the oil again. No oil. ?! No leaks, no blue smoke and no oil in the coolant. The filler cap had some sludge in it so I figured it gummed up and wasn't being pumped, or somehow burnt up or evaporated? A friend towed me to the highway and I called AMA... Before bed I drained the oil or what was left of it, refilled and started it up. Still knocking, and not idling properly... Will stall on its own in Park. I changed the oil again and went for a drive. The engine is knocking at a lower RPM now, basically 2000 and up, and has little power but feels balanced and sounds nearly perfect. No shakes or vibrations. I might be optimistic in wondering, but could a wet/dirty coilpack or plug cause a knock? My guess is bent piston arm or valve, or worse, even though any case is pretty much a write off with these things. Any help is much appreciated. The last engine I did this to has a two bent piston arms, and thats about as far as I looked at it, though it drank a lot of water, this one not so much.