Here is thread that explains it quite well by MT2500;
http://www.automotiveforums.com/vbul...essure+testing
Keyword for search is FUEL PRESSURE TESTING
There is a Schrader Valve on the fuel injector line (it has a black cap on it and resembles a tire valve stem principal)
Check with your local parts stores they may have one in their loan a tool program. (Checker, Autozone) If not Harbor freight has one reasonable price also parts stores have them for about $40.00.
If you do need to replace fuel pump use only AcDelco or Delphi fuel pump. Carquest now handles the Delphi pump
Feel free to ask more questions if necessary