Voltage issues

Again with the electrical problems.... :banghead:

The car in question is a 99 civic DX. I had some problems earlier this year that caused me to replace the alternator and battery. I picked up an Optima battery and a 135 A alternator, and they worked beautifully until recently, when I noticed a dip in the voltage. The voltmeter (autometer) is reading just over 12V, normal voltage was just over 14. The voltage will stay the same wether I'm running no accessories or have everything going, lights, heater, music turned up loud.

I checked the terminals, they have very little corrosion, just a tiny bit, but nothing major. Also, I checked the pulley belt, and it's nice and tight, deflection is normal. I'm also using the stock power wire from the alternator, could this be restricting the alternator? I was thinking I may upgrade it anyway, but I'd like to wait until after christmas if possible. Or maybe it's something else I'm just not seeing? Thanks again!

Anyone?

Beuller.....? Beuller.....?

Please help!

Upgrade the BIG 3. Replace your battery ground, valve cover ground and your alt to battery wire with 4 guage wiring.

Thanks. Will the 4 gauge wire fit the ring terminal on the stock alternator wire, or will I need to find a suitable replacement? IIRC, the ring part of the stock terminal wasn't very big, and the ring on a 4 gauge terminal probably won't fit.

Cars typically run off a 12v system, so technically your voltage shouldn't be much over 12v anyways, I wouldn't suspect anything wrong, as your voltage would have dropped quite significantly if any there was wrong.

Some mornings I'll start my car, and if REAL cold outside I'll show about 15.1 volts, pretty damn high for a car, but electricity flows better in the cold too. Then as I drive the car, the voltage usually drops off by 1.5 volts, as per the car's usage of electical resources for lights, radio, amps and of course the engine (spark plugs). If it's a hot day over say 85 outside (which is often here in CA) then my voltage will be about 12.5 to 13 volts when driving, and drop as low as 11.5v when at idle at a light. This is normal as well.

Thanks. Will the 4 gauge wire fit the ring terminal on the stock alternator wire, or will I need to find a suitable replacement? IIRC, the ring part of the stock terminal wasn't very big, and the ring on a 4 gauge terminal probably won't fit.
You'll need to find a replacement.

And yah just like the ^^ he said. Your car's electrical system is a 12 volt system. With the motor off you should see around 12 volts and with the car running it should jump up to about 14. Aslong as it's not dropping below 12 and going insanely higher than 14 you're okay.