Under what condition must a vehicle be rejected with regard to the evaporative emission system?

A vehicle must be rejected with regard to the evaporative emission system if components are leaking or improperly routed. This is crucial because the evaporative emission system is designed to prevent fuel vapors from escaping into the atmosphere, which is essential for both environmental protection and vehicle performance.

If there is a leak in any of the components, such as hoses, the fuel tank, or the charcoal canister, it could lead to an increase in emissions, which is not compliant with environmental regulations. Additionally, if the components are improperly routed, it can hinder the system's operation, also leading to potential leaks or failures.

Maintaining the integrity of the evaporative emission system is vital not only for legal compliance but also for ensuring that the vehicle operates efficiently and does not contribute to air pollution. Therefore, identifying and rejecting a vehicle based on leaks or improper routing in this system is a key part of the inspection process.