99 Blazer battery throwing sparks.

check your fuse box if theres a short look at the manual and see what fuse works with the battery after find a fuse that is not needed for example a windshield wiper fuse or something like that make sure the battery is off and so is the car after doing it check if it sparks again if it does then think about getting your battery replaced.

Make certain that you are not trying to hook up the battery backwards. Also check the large wire that goes to the starter and the big wire that goes to the alternator.

Make sure you don't have a wire pinched in between the head and block. Hope that helps! Jim

It was.... "" alternator hooked up wrong "" for the win.