if i put a meter across the battery on my rs turbo s2 i get 13.15 volts when engine idling, will not change if i increase the revs, if i measure the voltage when engine off it measures 12.4 volts. im pretty sure that the volts should rise to about 14 volts when increasing the revs, any ideas what the problem could be, have checked the earthing to the engine.

steve