starting issue

Total noob here hoping that someone can help out. Recently purchased a modded 07 mazdaspeed6. Previous owner said fuel injectors needed to be replaced (codes on accessport agreed with that as well) so that's what my dad and I did today. After replacing the injectors, we can NOT get the car to...

Have had troubles getting this thing started when I bought it but it would start after many cranks, But today when I was installing some new parts. I hooked it up to the jumper. Cables like I usually do and it started giving me a little bit troubles this time, I was cranking it over and then...