Voltage drops at idle raises on acceleration

[93GreenLX]

Any ideas what could cause my voltage to drop to 10 at idle and raise to normal while driving? And also what can fix it?

Thanks 93

 

[bhuff30]

a bad alternator could definatly do that.
They produce less voltage at idle anyway, and as they start to go out, and make less and less voltage, it becomes a bigger problem at low rpms.
Consider yourself lucky. All my alternator just cetch fire.

 

[93GreenLX]

Any other signs that the alternator might be going bad??

 

[bhuff30]

lights dim, car cranks slowly, when you turn the vent on high with the lights on, the voltage drops way down... when you have the alternator tested at your friendly parts store, it test 'bad'.

 

[nomuffler]

your blinkers will slow down.

 

[Paul C.]

I changed out the starter relay and fixed all kinds of voltage gremlins in my daughter's 91. $10..just a lucky guess! That was after new cables,battery and tested the alt!!