Also as your Toyota ages and with the constant starting over the years "ALL" of the electrical parts will wear out. The switch wears, the resistance in the actual wires, it is just a product of time. Now if you get your starter from Toyota and you are still having issues try adding in a relay to the switch at the starter. You can run a auxiliary light relay from the battery and use the ignition switch as the low voltage side. What this will do is turn the switch into the signal to activate the relay which will provide full power to the solenoid instead of the now reduced power that the aged system is supplying. I've had to do this on several rigs I've owned and it works like a charm.