My alternator gauge is acting strange in my 68 Charger R/T. At idle it is 0 to slightly minus, but recently it is going all the way to plus 40 when it get over 1500 rpm.
Every piece of wiring in the car is new Year one harnesses. I have the solid state voltage regulator that is in the original looking 68 style caseing. Alternator has 3 connections and it has a chrome ignition box, all which are new. What do I check first? Car runs fine and starts right up after driving it.