Q: Won't start when low on gas and with adding some gas it still won't start.

Hi there. When the fuel system gets low on fuel and the engine is still running and the engine stalls, there is a great possibility that the fuel system may have air in it. Put on a test line on the test port to your fuel system. If there is no test port, then remove the fuel quick disconnect from the fuel rail and put a tray under the line. Turn on the key and wait until fuel comes out of the line. It may take a few times for the key to be on to have fuel come out of the line. Then put the fuel lines back together and cycle the key on and off 3 times to make the fuel line have full pressure. Then crank the engine over and do not stop until the engine starts up. If the starter is engaged for more than 30 seconds, stop and let the starter cool off before doing it again. Make sure that the battery has a full charge before cranking the engine over. If you need further assistance with your engine not starting due to a lack of fuel transfer, then seek out a professional, such as one from Your Mechanic, to help you.