Vacuum pump question

[DAKOTAKIDD]

I recently swapped out my 92 eco diesel airbox with a 89 jetta diesel airbox.  My old setup had a vacuum line from the airbox to the vacuum pump.  I removed the line and should I cap that opening on the pump or leave it open to suck air.

I am not sure what the rest of the normal jetta diesels have on the pump but mine has a line to the firewall and one to the brake booster.  Does anyone have a 3rd nipple for vacuum or not?

Thx

[burn_your_money]

Cap it up.

The vacuum going to the firewall likely is for your HVAC controls. You have AC right?

[DAKOTAKIDD]

Yup, I do have AC

[DAKOTAKIDD]

TTT