not firing

okay ill explain a little more i bought the car about a year ago and havent had no problems with it up until about a week ago when i got it the engine light was on but car seem to run fine this is my first mitsubishi so im out of my element on it really and i parked the car as usual and went out to leave the next day and the car just spins over i mean this happen over night witch blows my mind cause iv never had one do that so first things first and since iv had it i havent done nothing to it but change the oil in it so originally i thought of a fuel problem and researched on it and found out that it does not have a fuel filter except the sock on the pump and also found out them cars do not prime until the car is actually in crank position so the pump it working but caint seem to find a fuel pressure valve to check the pressure so i pulled the cap off and the button and the cap and button was in very bad shape so i replaced the cap and button and still no fire out of the distributor and so automatically i thought of the crank sensor and when i unplug the crank sensor and plug it back in it makes a noise like its working something up top and so i was thinking about it and sometimes when i would crank it it would have like a little delay sometimes when it was running so as im trying to check for injector pulse to rule out the crank position sensor it stops turning over period so now iv got the starter of and i think it bad cause when i manually put 12 volts to the starter the gear dont come up it barley spins do you no if there are any common problems with these cars and how would i check for fuel pressure.