The 543 means the fuel circuit shut off because the engine stalled. It's a safety circuit in case you get into a wreck the fuel doesn't keep pumping. Seeing the car is a 95 like mine, I would look for vacuum leaks. Hardest one to find was the broken elbow on the PCV inlet. I did the U/L intakes and changed out various parts in the process like grommets on the IMRC, etc.
