Mitsubishi Repair: will not start, car fire, timing chain

Question
QUESTION: i am helping a friend fix his 91 mirage this could be important there is no air filter in it right know but it is not getting spark new distribute cap new rotor new plugs new wires it tries to go but will not turn over what are my next options could it be the alternator with that i thought there was just no power but i never worked on any cars but American and it is getting gas i read that no air filter will cause the ECU will not let the car fire because of to much air flow
ANSWER: Eric: I would have the car coded, sounds like a bad, weak sensor(s) or the computer it's self could be bad. The coding would rule any of that out. Then is no stark, is the timing belt good? All the alternator does is keeps the battery charged up, so gives power to the system. How old is the battery are you saying the engine turns over slow? If so how old is the starter? Your friend's car is in the right year for bad computers, Mitsubishi farmed out the building of their computers to another company, which did not build very good ones. With time a piece starts to leak into the computer and then kills off the computer. It will sometimes show up in the not starting as well as other things. Not having an air filter will not make the computer stop the engine from starting. But a bad sensor or more could do that. If you got an AutoZone close by, they will code your car for free. Other wise get a repair manual and a voltmeter see what kind of readings you get. The computer could stop the car from firing if a bad sensor or more someplace. But I would also check that timing chain or belt if that is bad or broken the car will not start then either. Hope this helps and good luck!

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QUESTION: i found out it is a 93 not a 91 and dont they sell a computer that codes the car and check things and will tell you because i cant get that car to turn over and i did check the fuses thanks for your help

Answer
Eric: You get a repair manual for your car. I have one sitting on the floor in my computer room. And a voltmeter, the repair manual will tell you the readings you need and you check the car out starting with the battery. Till you find the problem. My repair manual has code readings for a 1993 model car. I would say your intake air temperature sensor is out and maybe your barometric pressure sensor too. But I would find something to code the car or use that voltmeter. Because those two sensors new cost around $500.00. Of course you could go to a junk yard and buy them used. You can use any parts for your car from 1990 to 1994. No there is no computer you can buy that will code that year of car. Unless you take it to a shop someplace, they would be able to do this for you. Or you get that repair manual and a voltmeter. Fuses are not going to help you. It is either a sensor(s) or it is the timing belt or chain. Did you check that to make sure it is not broken? Two or three things can stop this import from getting stark, bad stark plug and wires, bad sensors or computer or both and a broken timing belt or chain. Not sure what this car has in it, but most have belts. Sears sells good voltmeters and most parts store will sell you a repair manual. The computer of that car gets all it's input from all the sensors all over the engine, in a few seconds that computer decides if the engine can start or not. If you believe it is the air filter why not put one in and try the car. I mean just an air filter the thing does not cost much, give it a shot! And I hope I am wrong about the sensors or the computer or even the timing belt. Because putting a timing belt into one these little car, is a pain in the butt. Excuse me, but it is. I do hope this helps you and good luck!