Replaced Catalytic Converter, but Camry smokes when starting up now??

Most likely suspect is valve seals leaking oil in the cylinders after car is parked for awhile!!

What color is the smoke?if its blueish gray could be engine oil being burned through the engine and you would be losing at least 1qt of oil between oil changes.If the color is darker almost black this would indicate engine getting to much fuel.If the color is white could indicate antifreeze being burned through the engine and you would notice coolant lost in the coolant reservoir.We can give you a second opinion call 760-757-9615 Cornerstone Automotive Oceanside Ca.