Voltage does not stay the same?
I noticed to today that my voltage gauge keeps
moving around alot, it bounces around from 14 to
15 volts and sitting parked it will have around 12 or
13, I suspect it's the alternator but im not for sure.
Is there anything else that could cause this?
Change your altenator.
The alternator has a built in voltage regulator. You should check the system with a voltage meter to verify the gage on the dash is correct. With the external voltage meter connect at the battery, start the engine and check the voltage. Before starting the engine, it should read about 12 volts. After starting the engine, it should increase to about 14 volts. You can also turn on the headlights and blower to see if the voltage remains above 13 or so with everything electric turned on. If the voltage jumps around on the voltage meter, you likely have an bad voltage regulator. Replacing the alternator should correct the problem. Also check the battery connections to make sure they are not corroded.
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