Volt booster???

[qws2000]

I have a volt booster, and when the car is idling the reading on the scan master is bouncing around so much the range being 12.8-13.5...... I also noticed when WOT it never hits any higher then 14.8 Is there anything wrong with the 200 amp alternator or Volt booster

 

[Raeban]

The measurement the scanmaster indicates goes through the ECM and a handful of connections along the way so it tends to be a little low. I would not be concerned with the voltage you are indicating.