Car cuts off when at a stop

Either theres a vacum leak, the mass air flow sensors bad, or the idle air control valve is clogged.

First i would start with checking fuel pressure and all the components related to fuel. Like doing a volume test, and checking the fuel pressure regulator. and or checking the fuel filter for blockage. (have to take off and blow through it, the harder to blow throught means its clogged).Test the spark plug wires with a spray bottle of water(if you see arcing, replace the wires) next check spark plugs ( again removal is the only way to see wear indications.) these are the easier checks to see if your car needs a tune-up or not. keep me posted. thanks jeff