fishy54

Hi can anyone help me ? I have recently bought a import s/20 sport forester, should this have a lambda sensor fitted as the front pipe has a blanking bung fitted.Would this make it hold back under acceleration or are they all like this? Sorry if i seem a bit thick ,but its the first import i have owned and i don't know the rules for japan. I have owned a prodrive wrx for 6 years so i do know my way around a scooby. Fishy54