I am the owner of a 2001 Camaro 3800 5speed. I've noticed that while driving, when I let off the gas to shift gears, the battery voltage gauge will drop from 14.5 volts to 13 and then will go back to to 14.5 volts. I replaced the battery and alternator about a year ago and have had no problems up until this point. I do have a subwoofer hooked up with an aftermarket deck , but I purchased a 750cca optima agm battery to help with powering the system. I don't know what is causing the drop in voltage and appreciate any input.

 

What you're experiencing is normal. So long as it doesn't drop to the 12 volt range (indicating you're running off battery only) or above 15 volts (indicating the voltage regulator has a problem), you are fine. Voltage will drop with different loads, different rpms, etc. You're fine.

Once the engine is started, all of your draw comes from the alternator, not the battery. Depending on the amount of RMS power your amp/sub is, it wouldn't hurt to either install a higher amp alternator or a capacitor. Normally though, if your system is drawing too much power, your lights will dim

 

what rpm is it idling at, does it drop more when shifting.

 

It idles at around 700rpms. I've also noticed that the battery gauge is at around 15.5 volts when I first start the car in the morning and goes down to 14.5 after it's warmed up. If I let the car sit for around 10 to 15 minutes idling while it's warm the voltage will drop to around 13.5 also. But the gauge only jumps back and forth when I let off the accelerator to downshift or if I'm braking coming to a stop. When I'm accelerating to get up to speed it never drops when I let off the gas and shift gears I don't think I mentioned that in the original post.

 

Thanks for the advice. Do you think it would help to bypass the stock monsoon amp to conserve power also? I've thought about doing this but haven't got around to doing it. its hard to tell if the lights dim because I replaced all of my interior light/dash lights with leds. I also have hid headlights. The battery gauge does seem to jump a little also if I'm driving and am playing a song with a lot of bass.

 

And one other thing is that when I start the car it takes a couple seconds for the alternator to kick in because the battery gauge stays at or slightly below 12 volts and then will jump up to 15 volts

 

voltage regulator may be goin south or the exciter wire could be getting bad connection. should be getting voltage to the little wire that goes to the alternator when the engine is running. it tells the alternator to come on.