My 2011 Sienna is starting, but won't last more than a second or two and it dies. We scanned for codes and none showed! Looking around online, people said check the MAF sensor. It looked good and I cleaned it, but no change. Then we opened the fuel line and tried starting it and gas barely dribbled rather than spraying so fuel pressure is very low. I replaced the relay switch, and, again, no change. Am I missing anything else before I pull out the gas tank and replace the $400 fuel pump?