It depends.
Is the sally port connected to an enclosed parking garage? If yes, then it should be considered a part of that parking garage like any other entrance into an enclosed parking garage. Separation would only be required per Section 508 depending on how mixed occupancies are handled.
Does the sally port connect open exterior spaces on each side? If yes, then the sally port may be considered a Group S-2, but it would not require ventilation if doors into and out of the sally port have sufficient open area to allow ventilation. If not, then you may want to consider ventilation if the vehicles remain running during the inspection and the doors are closed. Separation again would only be required per Section 508 depending on how mixed occupancies are handled.