YOU SAID:
I farted and a vicar almost slipped out
INTO JAPANESE
おならをして牧師が抜けそうになった
BACK INTO ENGLISH
I farted and the pastor almost passed out
INTO JAPANESE
おならしたら牧師が気絶しそうになった
BACK INTO ENGLISH
The pastor almost fainted when he farted
INTO JAPANESE
牧師はおならをしたら気絶しそうになった
BACK INTO ENGLISH
The pastor nearly passed out when he farted
INTO JAPANESE
牧師はおならをしたときに気絶しそうになった
BACK INTO ENGLISH
The pastor nearly passed out when he farted
That didn't even make that much sense in English.