1999 Ford Escort car cranks but does not start?

Car was working fine filled up with gas and died less than 1 mile later. Have replaced plugs, battery is charged, car will crank but will not turn over. Have tried using starter fluid on the throttle body, and put water remover in gas tank, still will not start. There is a humming electronic noise coming from the enclosed part (see pic) on the rear of the engine block near exhaust manifold (the one with the plug unplugged. No engine lights came on or anything else. I have good spark coming from the distributor pak. Any help would be greatly appreciated.