You could instead create a field like "data updated", and create an API Workflow that applies the change to a search of Cars where "data updated" is "no" and only does it for the first 500 entries; as part of the update, it sets "data updated" to "yes", and then scheduled the same API Workflow to run again 5 seconds later. When it runs again, it won't pick up the entries where "data updated" was already changed to "yes", so over time as the workflow runs again and again, it'll work through the list of all Cars.