95 taurus wagon wont start

I have a 95 taurus wagon that died while I was driving it. it just shut off and now wont start. It will crank but wont start. It has an after market alarm system on it with remote start. Before it died you would press a green button on the key fob to deactivate the alarm then start the car. If you didnt press the green button it wouldnt even crank. After it shut off the little red light on the dash that used to flash when the alarm deactivated, now stays on all the time. I dont know what kind of alarm it is but its a black box under the dash with a crap load of little wired on it. there is also two switches under there, one for deactivating the remote start when working under the hood, the other im not sure. flipping these switches has no effect on the problem. was told by some sorry shop that it was the fuel pump and after $400 it still wont start. any idea's would be greatly appreciated. I would hate to take it to an auto electric shop as the bill may be more than the car is worth.

please help if you can.
thanks