99 Jimmy Fires but wont start

I had it start and run just fine a week ago when i bought it but it needed an alternator and battery so i had it running off a boost. Today i went and got an alternator and battery for it and installed it now it wont start. When you turn the key it kinda fires then nothing and when you stop cranking it it trys to fire aswell but wont start. It might be doing this cause its to cold out but im not sure? any ideas would be great

is it throwing any obd codes? have you tried starting fluid? when was last tune up? (plugs wires caps etc)

How do i access and replace fuel injector spider on a gmc jimmy its a 96 with the 4.3L v6?

Remove the upper intake.

I don't know about codes but I think I might have figured it out. I thought ignition so I started with a new cap and rotor, that wasn't it but it did get it going and I noticed that it's arcing out accross the coil. So I think that is all there is wrong with it.