whether the Fourth Amendment forbids a pretextual seizure of a motorist based solely on probable cause due to an alleged obstructed tag?

Does the Fourth Amendment require law enforcement officers to demonstrate a threat to their safety or a need to preserve evidence related to the crime of arrest in order to justify a warrantless vehicular search incident to arrest conducted after he is told he could leave but the officers continue to walk around?

Whether the Fourth Amendment prohibits law enforcement officers from conducting a warrantless search and seizure of a vehicle based solely on probable cause