general problems of the 1996 Nissan Sentra

Gas fuel leaks out of my port when I am parked face up on a 15 degree hill on a sunny day. The spilled gas creates a serious fire and health hazard. I have taken my car to a local authorized Nissan dealer more than four times to fix the problem, but the problem still continues. *****dimsii ivoq entry posted after 12/12/02 cut-over to artemis****734338.