I'm glad to hear some progress and hear it's runing now. Now the reason why the car is runing with no fuse pump is because there's was so much fuel that didn't burn. Your best bet now is to let it burn completly. As for seafom in the gas you can put some in but nissan injects are hard to clog but still good to clean the fuel system. The o2 is coming on because of the fuel exiting out exhaust and fouling on the o2. You can delete the code and pull the o2 out and cleaning it. Put it back in.