Why wont me car start?

Check all battery connections they must be clean and tight. Also check the negative battery cable connections on the frame and motor they too must be clean and tight. If all that checks out have starter tested.

Conections or starter solinoid could be bad or the starter it self. But check all connections first before going through the expense of the starter

yes. A coarse wirebrush and pliers will save the day if you undo the 1/0awg Black cable where it attaches and wire brush the lug and spot where it bolts...to restore proper grounding~

as dandyoun already said...if I even bothered to read it~