the engine runs fine regardless if the vacuum line is hooked up or not. I took out the booster today and sucked on that nipple that goes to the intake. It was like blowing into a coke bottle but just the opposite. I can suck in very, very little air. Matt and I are thinking it's the booster. Regardless I went and ordered a new one for 154. Questoin though. That metal arm coming out of the booster that hooks on to the brake pedal. Was that suppose to stay on the brake booster or come off too? Because I turned the core in with that arm attached to it.