I have a 2001 Pontiac Montana, 3. somthing engine. It recently started to die on me like its running out of gas. The gas gauge bounces around and the digital miles left thing bounces too. But ill be driving and then itll start to stutter, and then die like its out of gas even though I just put 20 bucks in it. Just trying to figure out if its the sensor, level sensor, pressure regulator, pump or somthing else. Thank you in advance for all your help.