When I'm running under power its fine

but at idle... it acts like a madman...

It also does it a bit with the turn signals.. but that's minor...

these are like huge fluctuations, do coincide with the idle (which is rough) and it only happens when its up to temp..

it's never really idled great, but this is way worse

radio has a whine too.

it all started when.... I put it on the charger and I got the B & R backwards... busted the charger...

where might I start looking for the problem?

 

i would really consider poping out the alternator and getting it checked out for free at the local Advance Auto Parts (if you have t hem over there), my mom's 89 chevy astro van's volt meter would go up and down even after new battery.

apparently it was the voltage regulator in the alternator which was going out and would cause unstable charing volts.

 

Actually, i have the same problem! And it's gotten SO bad, that now, when I hit a bump, the whole electrical system dims! Its fine when cold and under load, but the hotter it gets, and the slower the engine runs, the worse the 'flutter' And i've been thru THREE alternators! I have made NO mods to my system at all, and we can't find any loose wires. It's also hard to test for this, because the vehicle has to be moving.... If you find a solution, I'd love to hear it!

 

A reverse polarity situation can damage the regulator hybrid IC located inside the alt causing it to run wild, or based on the whine you hear you may have blown a couple of diodes in the rectifier pack also inside the alt. A voltmeter is handy for tests. You mentioned a charger, was the battery low or bad? A bad battery will many times affect alt operation and will cause a whine since the battery is actually a large filter capacitor for the alt. Heres a list of thing to look for on a TG, first check all grounds- don't just look at them, remove them and clean them. On side terminal batteries the plastic cover that the bolt goes through to attach to the battery HIDES corrosion. When it's running have someone watch the guage and wiggle both battery connections. Voltage fluctuation means there is probably internal corrosion you can't see. Next, use a heavy rubber mallet and bang the alt and see if there is a voltage change. If there is suspect the alt and check to see if the rear post is loose-if it moves at all you are losing your output connection from the rectifier pack. Next, with the alt off if it is a CS unit remove the plastic cover that protects the soldered stator connections. There are 3 crimped and soldered joints. Inspect each one to see if the stator wire is loose inside the joint or the solder has melted. It will cause you to lose a phase resulting in low output and many times they burn. The dash panel connector can give crazy reading as will the guage. Remove the guage(2 fasteners and it will pull out) and remove the 2 hex nuts on the rear of the guage and take off the white ceramic resistor. If the fasteners are loose and the connection on the resistor looks black clean it with alcohol(not beer) then remount it. Don't overtighten it, you can crack it. Before you remount the guage clean the two finger contacts with alcohol or any decent contact cleaner and gently squeeze them together so the guage fits in tight. Other than that the standard wiggle test on harness should reveal most intermittents. Don't forget the starter positve cable junction, that is a tie point for several fuse links to various circuits. LOL

 

As to what happened, went to going out... car wouldn't start, in the dark, got the charger cables backwards..

ended up fixing the problem (was vats, one of the wires to the key cyllinder broke off)

and then have had this problem ever since...

I'm replacing the instrument panel for several reasons, and the stereo as well...

I just need to fix the real problem (and the idle)

 

Then I would suspect the alt, most likely it got damaged.