Voltage problem

[87'N/A]

My voltage gauge has been bouncing back and forth from about 13-16. Sometimes it will even spike to over 18. It started happening right after i replaced my alternator so i think that's the problem but just to make sure what other things could be causing this to happen?

p.s. I know it's not a problem with the gauge itself because when the volts go up and down on the gauge the headlights/any lights on the dash will get brighter/dimmer.

 

[87'N/A]

uhh...anybody??

 

[Nick M]

Why did you replace the alternator? Did you put a Fluke on the battery and watch it? How about on the alternator output?

 

[87'N/A]

because the alternator wasn't working anymore and my car wouldn't start. and a fluke?

 

[Nick M]

Fluke makes digitial volt and ohm meters, commonly called multimeters. For diagnostic purposes. Is it a remanufactured alternator from Toyota, or an autozone special? How is the wiring to the alternator?