Two problems related to car will not start have been reported for the 2003 Infiniti G35. The most recently reported issues are listed below.
I was filling gas up suddently my car did not want to start. My check engine light soon when on. When I started driving my car was moving poorly. My engine light when on after. I when to autozone to check my code. They said it was due too camshaft senors.
Something was draining the battery in the electrical system. One day while trying to start the car after it had been sitting for a few days, everything flickered (headlights, dashlights, control panel) and then the car wouldn't start. Charged the battery and then the radio, ac/heater/defroster did not work properly. Have seen many similar complaints on the internet.