[frankym]

if this is a customer's car, was there a loud noise heard before the other symptoms surfaced? Could a single connecting rod have snapped? I would think it would continue to make a lot of noise while engine is running, but if it broke from the crank end, and the piston was near the top of the stroke, could it be that when the plug is removed, and a long screwdriver is inserted, the position of the piston is unchanged at sitting at the top after running? If the piston is moving with the rest of the crank, and the valves are all opening and closing, sounds like there's still some missing information about what happened prior to noticing the current problem.