Vacuum Test
there are 3 holes on the back of the intake manifold, 1 for break booster, 1 for map sensor and im not sure what the other was, on my car it now goes to a map sensor.
2 off the sides near the throttle body, and another near the top passangers side by the throttle body. Also there is the EGR hole. If all of thoes are connected you should be fine for vac

