bmw 316 - vacuum pipe - bryer

Hi lads I am looking for your help with my 316 pierburg carb the thing is that I have a small vacuum pipe that goes through the bulk head but after that i dont know where it goes, the car is running lumpy so help needed cheers bryer.

bmw 316 - vacuum pipe - Collos25

Could be the feed for the MPG gauge in the speedometer on earlier models this was run of the vacuum system.

bmw 316 - vacuum pipe - bryer

Thanks for your reply,but the car is running bad and mpg gauge is fine??

bmw 316 - vacuum pipe - Collos25

Thats not the problem then,there are hundreds of reasons why a car engine runs rough as you say its a process of iimination or take it to a BMW specialist.