2000 Oldsmobile Silhouette no start

Hi I mhave a 2000 oldsmobile minivan silhouette. The other day I was repairing rear tail lamp with vehicle running, after a while car shut down by itself, try to restart engine and it took a while and several cranks to start. Shut off and restart w no problem, drove vehicle to autopart store and when I want it to restart vehicle again it wouldnt start. Same thing it took long to crank then start it. 3 days pass and it start just fine. 4th day it wouldnt start. Replace fuel pump with new unit at this time new pump had new upgraded harness which I install following the instructions. Install pump in tank. Want it to start and it wouldnt start. Check fuse at enginebay and good check relay and ok. Remove connector at pump and no power or ground at harness
went to connector right under drivers door and foudn corrosion clean it up and found some pins corroded clean and replace bad pins. Still no start. Check for power at grey wire at connector and none present. Please help.