求翻译：The COC applications for the engine families listed in Attachment A state that there are no adjustable parameters on the engine families for these A TV s. However, EPA inspectors determined the carburetors ofthe sampled ATVs had removable main jets, pilot jets, or a jet needle with five clip-position grooves. These features allow adjustment of the engine's air-fuel ratio, and if adjusted, may affect emissions or engine performance during emission testing or normal in-use operation.是什么意思？

待解决 悬赏分：1 - 离问题结束还有