Power Surges?

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Super Moderator
recently, my motor has been "surging" when idling, almost sounds like its breathing like an animal (best way to describe it, lol) reving from 800 to 1200 back to 800, constantly... i've also noticed, that my headlights and interior lights will "surge" not with the "breathing" style of idling, but it does surge, and the frequency of the surging seems to speed up (the lights surging) when the motor revs up. sometimes after drviving for a while, the lights will stay steady, and then the "breathing" type idle will intermittently go away..?? what is going on here? also, it seems that it affects the power delivery of the motor, like, if i'm driving in first, slow, like in a parking lot, the power surges with the light surge, but when highway driving, it is not noticable. I have a feeling it is my alternator doing this, because of a stupid AEM pulley on it. do you think a simple alternator test would be able to tell me what is going on? i dont want to replace the alternator to just "see" if it changes anything. has anyone else ran into this problem? it doesn't seem to affect the display on my radio or vafc, when the other interior lights and headlights are surging. i'll stop by an auto place and have them test it, can they test it while its in the car? or do i have to take it out?
the power surging was due to the alternator, stupid AEM pulley, never get one!
the idle surging was due to a cracked vacuum line from the fpr to the intake manifold.
thanks for all your help guys, lol!