Vacuum pump installation April 06, 2021, 03:28:04 pm So sometimes the simplest things can make me scratch my head in puzzlement. I ordered a dorman 904-214 vacuum generator based on recommendations of people in this forum to replace my aging and rusted out vacuum generator as possible fix for my dash temperature controls not working properly.And I'm a little puzzled with one of the connections. There was an airline going to one side of the vacuum generator and on the foretravel model there is a push in connector for that line. On the dorman there is only a plastic piece with a lip on the end. I'm not familiar with that type of a fitting.So questions are number one what's that fitting for and how do I connect an airline to it?Number two why is there an airline going to the vacuum pump on our coaches? if it's just producing vacuum for the dash gauges what's it doing with compressed air going to it?