We have a 1990 Ford Ranger - 2WD 4cyl - sometimes when we try to start it, it will not kick over the final time for several tries. When it finally catches the voltage gauge will flicker and jump around. When the gauge flickers, the truck will shut off…then the same issue with trying to start it again. Some days it runs just fine and others it will stall out 3-5 times in a 15-20 minute drive. We have been told it’s the DIS Module OR the Crankshaft Position Sensor OR the Voltage Regulator OR … any ideas would be greatly appreciated
Do you have a check engine light?
Assuming the CEL is not on, and the routine maintenance is up to date. If not, get that all done first. The first thing I’d check is the battery, battery connections, and charging system. Of the three possibles you list, in a 1990 Ford? My first guess would be that the crank sensor is on the fritz. Is the engine splash guard still in place and undamaged? The crank sensor really takes a beating anyway just because where it is located, and it is worse when the splash guard isn’t working like it should to prevent mud and water from spraying up from the road on it.