Looking to fit a boost gauge on a friends V70 T5 and on the vaccum tree does it matter if one port is exposed without being covered by a cap? Or would that cause issues? Was thinking of just plumbing the boost gauge line in there without using any of the others.
Only remove the cap if you're planning to replace it with something i.e. goost gauge hose.
Theres one already exposed without a cap, the car has a slight idle problem would that cause it? I know it sounds silly but is one supposed to be uncovered?
Nope. All supposed to be sealed. This may cause an idle problem but would deffo cause boost problems with the actuator or recirc valve.
Your a star and such a quick response, even at this ungodly hour of the night. I'll use the exposed one for the boost gauge then, thank you.