Car Won't Start-Sometimes

if "all conections are good" and clean and your still having this probblem its one of two things. odds are 95% you have a bad starter cylinoid. on the off chance you may have a bad spot in the starter .

p.s. if you can pull the starter and cylinoide yourself ,a place like autozone can test them for free and supply you with new on the spot.

You might need a new battery cable. Even if the connections look good, the cable can wear out and corrode inside of the insulation. I need to replace the ground (-) cable on my car one of these days...

Fault Key light coming on? From what I have gathered (so far), it may be a bad chip in the key that is making intermittent contact, as the wires began to wear over the years.