Crank but no start

I installed alternator sometime after i  start driving
car after i bought it over a year ago changed one
engine coil and did oil change and spark plugs and
wires. Im not sure if i tampered with cigarette
lighter in front too much but it went out once or
twice so i dont use it. One day the air stop blowing
cold ... One day i got off from work and the horn
was sounding off. I drove the car home then i
unplugged horn hookups on both sides. Then my
cluster went out. I can see oil lights etc on very top
but i cant see speed limit or maintenance stuff. I
drove car like that for some time before replacing
pcm (i sent vin# so it's suppose to be
programmed) and the lights still didnt work for
speed limit nor maintenance. But the horn works.  
My heater core went out before i could test ac. I
replaced heater core w a new one. The the car was
running hot ( i forgot to mention) but i dont think it
is anymore now that I've replace heater core and
and it has antifreeze in it. Still havent tested ac. I
had my uncle replace my thermostat w a new one.
He also replace waterpump. All of a sudden the car
turns over but wont start. I've. Chaned ignition coil
on far left (passenger side) bc it didnt light up like
the other three.That  Didnt work! I added a few new
fuses even tho test light lights up for every fuse. I
changed IGN1 fuse in the trunk' still no start. I
changed IGN1 fuse under hood\no start. I changed
BATT1 fuse\ no start. I went over one day and i
realized unc had been leaving the key in ignition
day in and day out. So i removed it.