Alternator-related question
 

At idle, sound system off, if you hook up a voltmeter and turn the headlights off for a few seconds, then turn them on... how long should the voltage drop until the alternator catches up and raises it?

I just did this experiment on my car a few minutes ago and it takes almost 2 seconds for voltage to rise from ~12.5V to ~13.8-14.0V after I turn the headlights on while merely idling (no accelerator pedal assistance)
It recovers immediately if I have the engine revved up a little.


Other items to note: The car has 105K miles on it, original alternator, however it has an Autozone battery I bought this past January. The past 2 times I've taken my car in for alignment, the mechanics run a battery test (along with basic inspection of the wiper blades, drivebelts, etc.) and the test always shows that my battery's "health is low" (whatever that means--their machine has some printout... the printout has EXIDE written on it, maybe someone's familiar with those things?)
The battery sits with engine off at 12.5V, rises immediately to ~13.5-14.0V with the engine running.

do you have an underdrive pully? this may be related if you do.

also try a grounding kit, it could just be that you have alot of resistance.

Grounding kit, yes, UDP, no.