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Don't have a 3v but the first thing I'd do is check oil level & pressure. Then go hunting with a stethoscope at idle. If the oil pump isn't pumping much for any reason you may have an expensive door stop on your hands.
Not a good idea to rev engines that obviously have mechanical problems, unless your pockets are lined with gold....
Check engine light on?..... Check all your ignition coils to see if any of them have blasted off. Try to move them to see if they are loose. Any other symptoms?