I have a 68 coup w/289. Recently I notice eveytime I use the turn signals the alternator needle goes down when the signal light goes on. I have a new battery and changed the voltage regulator but this is still happening. Also, put in a new turn signal switch back last March. I have turn signals in the hood and that wiring is new. Any ideas as to what is causing this?

Thanks

 

It's not a problem. When any lights energize the electrical load increases, and the bouncing is the circuit making adjustments.

 

has same issue when I replaced mine, needle would swing with the turn signals, when back to auto zone and got one from anothe manufactorer and it stoped swinging back and forth, both cases volts at battery were fine, the "newest" one was approx 1/2" taller and had some kinda resister/electronic choke? in that extra 1'2" area AT THE BASE THAT YOU COULD SEE IT,, I guess that's someones idea of how to fix a wild and swingen needle

 

Could be the alternator as well, starting to lose output if it's going bad. Take it to autozone etc and have it tested, if it's fine I wouldn't worry. Ammeters suck anyway, since all it's reading is a current flow. Voltage will tell you more, and as long as the voltage is good you're fine. If you have good voltage you have current, but just cuz you have current flow(at the ammeter)doesn't mean you have good voltage.

http://www.egauges.com/ATM_Tips.asp?...terammeter.htm

 

Check the gounds (esp. body-to-battery ground).

 

+1 to Oxnard,

Unless its bothering you leave it alone. The ammeter needle is supposed to wiggle when the electrical load changes. Your gauge may be more sensitve than others but that don't mean anything is wrong.