If a vehicle has more than one gas cap, what is the testing requirement?

When a vehicle is equipped with more than one gas cap, the requirement is to test all gas caps to ensure that they pass the emissions testing criteria. This is because each gas cap contributes to the integrity of the vehicle's fuel system and emissions control. A faulty gas cap can lead to increased evaporative emissions, which can negatively impact air quality and violate environmental regulations.

Testing all gas caps ensures that any potential leaks are identified and addressed. If only one or two gas caps were tested, it could allow for other gas caps that may not seal properly to go unnoticed, compromising the vehicle's overall emissions performance. Therefore, the requirement to test all gas caps ensures a thorough evaluation of the vehicle's emissions system, aligning with the goal of maximizing environmental protection and compliance with regulations.