Car won't start, stumped :(?

Your battery must measure more than 9.6 Volts across the battery terminals WHILE the engine is being cranked over in order to power the computer, fuel pump, sensors etc. If your battery is over 4 or 5 years old, you need a new one regardless of any other reason your engine won't start. Your battery cables need to be disconnected and cleaned inside the metal contacts with a battery wire brush when you install the new battery.