Can you put a carburetor on throttle body motor and still pass emissions?

No, you cannot put a carburetor on a throttle body-injected motor and expect to pass emissions. The engine management system (ECM) in a throttle-body injected vehicle is specifically designed to work with the throttle body and its associated sensors. Swapping to a carburetor completely removes this system and its ability to control fuel delivery and ignition timing precisely for emissions compliance.

A carburetor doesn't have the same level of precision in fuel delivery and air/fuel mixture control as a modern fuel injection system. This would lead to significantly higher emissions of pollutants like hydrocarbons, carbon monoxide, and nitrogen oxides, causing a failure of the emissions test. Furthermore, the engine's timing might not be correctly managed without the ECM's input, further exacerbating the emission issues.