For some odd reason my cars power gage is in caution after its running for awhile and gets in the yellow even faster if the AC is on I have replaced the battery with one of those red cap power cell batteries and replaced the alternator and it helped a little bit when I have the ac on it goes into the yellow I took out my my subs and it still does it idk if it could be adio related any suggestions

 

Is it possible the engine has an underdrive pulley system? That will put the voltage guage into the red at idle in hot weather with the AC on.

 

My car did the same thing (when it was stock) until I put in an Optima red top. It may be an annoyance to see your headlights dim, but won't damage anything. Like Injuneer said, it's possible a previous owner put in an underdrive crank pulley without an overdrive alternator pulley, check for that. Check your battery cables, wires to alternator, and chassis grounding straps. If nothing is wrong there I wouldn't worry too much about it.

 

I replaced my battery with the red top optimum battery and checked all the grounds and conections to the battery and alternator and still the same thing the reason why I think its audio related is because I replaced all my speakers and deck and still is on the monsoon amp and sometimes if the car is running and the music is up a little and it will cut out snd its not the deck cause my subs still work but the speakers shut off. So to make them turn on I have to turn off the car or somtimes out throw the car in neutral and back into gear really fast then it will come back on. Do you think that could have anything to do with it

 

Sounds like your alternator is not making enough power at idle to meet the electrical needs of the engine + the audio system. You need to find out why. I mentioned the U/D pulley issue. You may have an idle speed that is too low. Or you may have a lot of corrosion in the wiring to the battery that is causing power loss.