Strange Discovery - Fuel pressure regulator vacuum hose?

[e21rana]

I was doing a general check up on the pipes to see any cracks or worn pipes because my idling was lagging as I revved. I discovered a small metal ball bearing ball in the vacuum pipe of the fuel pressure regulator (the vacuum pipe that goes from the intake head to the FPR) what could the ball be there for?

[polov8]

Sounds like a previous bodge to me, I'd remove the ball or swap the pipe and try it like that.