[Locobob]

Are you sure all of that oil is being burned? I had a similar problem with oil loss and most of it turned out to be leaks. It had me fooled for a while as I never saw a drop of oil on the garage floor. As far as the emissions problem goes I would think you'd have failed on Hydrocarbons as well NOX if the cats were bad but then again I'm not exactly an expert on this subject. I've heard that California has tightened their testing standards since the cars were new, could be an issue here. If I were in your shoes I think I'd check the plugwires and coil packs next. You can also use a pyrometer to check if the converters are working - exhaust gas should be hotter exiting the converter if it's working.