My 99 Jetta with 74K miles has suddenly died three times within the last couple of weeks. The first time this happened i was able to immediately turn the ignition, glow plug light went on, restarted the engine and was off and running. The second and third time the glow plug light would not come on until several minutes had elapsed. I might mention that on one occasion while driving at highway speed, the engine did a split second hesitation, the glow plug light went on for a split second as well. Need help. Wife was driving two of the three times! One other question. Air in the fuel line. What is normal? Absolutely none? A little? I have noticed air in the fuel line after replacing the fuel filter. After reading some threads it appears that enough air in the fuel can cause the engine to suddenly die, but what explains the glow plug light failing to coming on when attempting to restart? Your help would be greatly appreciated.