When hose is connected to MAF(?) sensor, car cuts off; when hose is removed from sensor but still connected to engine, car runs. Bought new MAF, before installing, made connections and the car cut off. Any suggestions?

The MAF senses how much air in volume is getting to the engine. When disconnected it goes to a rich mixture by default on the computer. Check for an too lean mixture. Could be a vacuum leak, leaky PCV valve, dirty Idle Air Control (IAC) or a bad gasket on the intake plenum.