My 1992 Jetta GTX 16 valve 2liter, sat for 2 days and now she will turn over very well, but does not start. New battery, I checked the dist. cap and rotor,they are good. The gas tank is 1/2 full. Is there a fuel lift pump that is weak? or some kind of valve that is letting the gas flow back into the tank? or could this be a dirty fuel filter?

 

when the key is in the on position before its in the start position do you hear the fuel pump kick on ? If not check fuses and relays, if it is coming on replace the fuel filter

 

take out your rear seat and take the cover off the fuel pump... put the key forward and put your hand on the fuel pump if it doesn't vibrate you probably got a stuck fuel punp...