1990 Nissan 240SX shut down

Engine problem
1990 Nissan 240SX 4 cyl 120000 miles

My car sometimes will idle low which in turn sets off my oil indicator light and sometimes when I give it gas it shuts off. Also when driving if I go from a high gear to a low gear the car shuts down and when I try to restart it doesn't always start and I smell a strong fuel smell can you please help