91 Gp voltage drop when starting

I have 91 GP 3.1 when u start it it wants to fire but votage goes away but the starter keeps working. :banghead: checked all gound connections i could find and cleaned swapped sensors out . wondering if it might be in ignition switch? any ideas please had car for 3 yrs want to keep.

Can you give more information? Where are you losing voltage? It is normal for voltage to drop when starting. The starter is taking the majority from the battery. If it is dropping too low you may have a bad battery or a bad wire. Wires often go bad internally and you can't see the issue just from looking at them. Resistance in the wire increases to the point where the amperage goes so low that nothing will work. Try checking the battery and the wires.