Can a car stop running if the starter goes bad?

Yes, a bad starter can prevent a car from starting, effectively stopping it from running. The starter motor is responsible for cranking the engine to get it going. If it fails, the engine won't turn over, even if everything else is working correctly. However, the car *could* still be running *if it was already running* before the starter failed; the starter isn't needed to keep an engine running once it's already started.