Can you put a throttle body spacer on tbi engine?

No, you cannot put a throttle body spacer on a TBI (Throttle Body Injection) engine in the same way you would on a port-injected engine. TBI systems don't have a separate throttle body and intake manifold like port injection. The throttle body *is* the intake manifold. A spacer would essentially be blocking the airflow and causing significant problems, likely leading to a very rough running engine or no running engine at all.