Mitsubishi Repair: non start of 95 non turbo eclipse, mitsubishi eclipse, faulty computer

Question
We purchased a 95 mitsubishi eclipse used and have numerous problems with it.  We have replaced the computer as well as all relays to the computer.  The complete cooling system, fuel filters and all other filters.  Now we had problems with it not starting.  It is acting like it was the starter so we replaced the starter.  Spent numerous hours trying to start it and pretty much so gave up.  Then a day later went in and it started right up.  We called the dealership that did the previous work, drove it to them (tried to stale a couple times but made it) and they could not find a problem at all.  The car has been stalling at red lights and acting like it wants to stale driving on the interstate.  Anyway, the dealership called and said they could not find anything wrong and to come get the car.  We went to pick up the car and it will again not start.  They have tried for a week to get it started changed the plugs etc., but they can not get it started.  Now they are saying it has a cracked head and that the water is going right back into the overflow tank.  They said it is acting like it wants to start but it just will not turn over.  Any ideas?  Do you think it is the head or do you think is goes back to possibly a faulty computer, or a coil?  They put three computers in it before they found one that worked.  Also, would it be cheaper to just purchase a new engine and have someone put it in than to replace the head?  If so any idea where I can go to get an engine...  Sorry for all the questions, but I feel the dealership is just trying to cover themselves and not replace something that might be under warranty...  HELP !!!!! Thank you in advance.  

Answer
Crystal: I would look at the computer, are you sure they put the right one in for your car? Here is some ideas my book says to look at. This is a manual for Mitsubishi, which I bought at a parts store. I got into trouble of late for some of my answers and I want you to know; I take them out of a manual for these cars. If I read your question you say that first it would not start, you replaced a lot of things and then one day it just started. By looking at the wiring for typical starting system wiring diagram, going like this and I do not know if the car is an auto or a clutch so I shall send both... battery,there is a starter relay, oh but the key has to be turned, so then your park neutral position switch has to be working, then another relay, to the starter. With the clutch; key or ignition switch, starter relay, but then the clutch pedal position switch and again the starter but also battery. How are your switches, such as the ignition switch? the clutch pedal position switch and the park neutral position switch? Could be a relay that it has a shorted wire in it and for someday it touches what it should and other days does not. I don't think it is a cracked head, is there water in the oil? Or maybe they cracked it while trying to start it. How about the timing belt? Or the timing could be off. I know I replaced a timing belt but did not get the timing set right. The car wanted to start but would not. I would try a lot of other things before replacing the engine. I had another person write to me, but replaced the engine but that did not help him either. But in your case it might, I think I would try checking the starting wiring first, is the engine rotating when trying to start or not? How about the fuel pump? If your fuel pump is not pumping enough fuel then your car will not start. Pressure regulator? Ignition components damaged, broken, loose or disconnected wiring in starting circuit, crank angle sensor is changing the ignition timing that is in the distributor. Broken, loose or disconnected wires at the ignition coil or faulty coil all from my book. Ok, they replaced the computer did they then code the car to make sure some sensor is not out? The computer is only as good as all it's sensors are working. I hope this helps you, have a good Thanksgiving and good luck!