Technical What could I done wrong

A digital meter will pick up all sorts of spurious interference from the plugs leads, points, anything which is changing or turning on and off. About the only thing you can do is extend the leads by a metre or so, so that the meter is a few feet away from the motor.
An old style moving coil meter is the only reliable meter when the engine is running.

 

So this is probably nothing to worry about.

 

Solar flares ??

 

"An old style moving coil meter is the only reliable meter when the engine is running".............. also known as a "shunt".... type meter...... uses windings and then resistors for multipliers....

 

Even spiral wound wires and resistor plugs, a generator w/mechanical regulator will wipe out AM band frequencies. My old truck sounds like a blender over the radio.

 

Brought my meter home from work and it was reading 15 volts and not that crazy 125 volts like my other meter so I think I have nothing to worry about,when you have a meter reading over 120 volts on a 12 volt battery it can make you worry a little. From now on I am going to use the meter on the load tester when the motor is running since my digital meter got my blood pressure up a bunch.