When things settle down, you need to determine why you have lower than normal voltage at the coil. How confident are you in your meter accuracy? If you think it's reading a few volts low, you may be OK. When my car is running I think I am getting 8-9 volts to the pos terminal of the coil and about 14.5 at the battery. Do you have an ohm meter? If you do you can disconnect the battery and check resistance from the battery positive connector through the starter relay terminal, through the bulkhead connector, and through all connectors to see if you have any poor connections out to the coil.
Ron