Ok trying to work out what car this is mk3 or mk4!
Your VIN doesnt sound right a Golf will start off with WVWZZZ then 1H for Golf 3 or 1J for Golf 4
The X suggests a 1999 model but Golf 3 finished in 1998, June 1998 was the last one that was built.
ABA suggests its the 16V engine that came only in mk3 Golfs
Id suggest removing the fuel rail complete with injectors unplugging the injectors and checking to see if there is any leakage through the injectors
Also check your fuel pressure, maybe change the filter?