91.112—Requirement of certification—adjustable parameters.
(a)
Engines equipped with adjustable parameters must comply with all requirements of this subpart for any adjustment in the physically available range.
(b)
An operating parameter is not considered adjustable if it is permanently sealed by the manufacturer or otherwise not normally accessible using ordinary tools.
(c)
The Administrator may require that adjustable parameters be set to any specification within the adjustable range during certification, production line testing, selective enforcement auditing or any in-use testing to determine compliance with the requirements of this part.