Toyota 1998 Carib 1.6L using excessive engine oil?? Well maintained and looked after car can't understand y?

If not smoking from tailpipe the check all around engine compartment and undercarraige for leaks. if engine is burning oil there will be some smoke light blue in color. maybe too light too see but you can always quickly sniff around tailpipe oil smells oily when burned but if the engine is burning it badly there will be enough smoke to see. this means either bad seals around the valves in the engine head or bad rings on the pistons. do a compression test for rings. if compression is equally high then the problem is in the head's valve seals get a valve job. how many miles on vehicle? hit me at [email protected].

Well for starters, that oil has to be going somewhere, obviously.  So most likely it is the piston rings, these wear out over time regardless of how well taken care of your car is.  Check the exhaust out while the car is running, if there is a white-blueish smoke, thats piston rings.  if it is more grey-ish, thats most likely a head gasket, in which case check the coolant overflow for color, and remove the oil filler cap and look on the inside, if you see a nasty looking white film, thats caused by water/coolant in the oil, most likely leaking through a bad head gasket.  Or it may be leaking out somewhere, if there are no puddles it may be leaking near a hot exhaust pipe/manifold and burning off.  
As long as you keep enough oil in it, it should be fine for a few years, just get it fixed eventually.  in the mean time you can also use oil additives to help string things along, ask the rep at your local auto parts store.  hope this helps!