Alright I'm new here but I need some help... so I recently bought car and it didn't have a battery but once I put the battery crank no start, I also did the spark plugs and 12v FP mod and now it won't crank at all like my anti theft system is engaged but I try to do the reset procedure where I lock all doors and what for 30 seconds or so but the security light doesn't flash and I've disconnected the POS terminal and then put Iit back on then the alarm goes off but still won't crank I've try both keys and I don't what to do.

 

I would suggest get the battery checked for drain at a local shop or store. If you didn't wait long enough time for the power to drain whem you did electrical then the battery may be drained when you reconnect it. You can ask me how I know... hopefully this will help you out.