1994 ford aerostar starting problems?

If the engine cranks over, but will not start or is difficult to start, it's either fuel or ignition. Too many possible causes to list. A repair shop which can extract engine codes and accurately diagnose problem. Simple things to try: 1. check clogged air filter 2. check clogged fuel filter 3. check worn out plugs, cap, rotor 4. examine vacuum hoses for leaks