Quote Originally Posted by Storm Trooper View Post
With the 470 ohm resister between your sense and your sorce. Your alternator should put out steady it should not fluctuate. Also if you have a bad ground your alternator will not put out correctly. Did I say check your ground? :-)
On your advice, removed the harness ground from the block, sanded it down, cleaned it with goo, and refastened.

Swapped the MSD plug wires with autozone specials, since that's all I could get today for diagnosis purposes. Got the old wires off, ohm'd them out... suspense... 8 out of 9 were bad (two orders of magnitude low on resistance), and the 9th is questionable at best.

Two of the wires looked like this!
IMG_20160929_212354.jpg

Unfortunately the set I got from autozone was missing the coil wire, so I used the questionable MSD wire for testing on the coil. New coil wire will be here tomorrow for further testing.

Fired up the car and the tach isn't bouncing around any more, getting an occasional wobble that I'm hoping will be fixed by swapping the coil wire. Alternator isn't getting stupidly hot like it used to, ICM is getting hot but I can actually touch it (not at all possible before). I didn't think it was possible for these wires to be bad, could have sworn we changed them this year.

I'll probably try to get a better set of wires for TWS, swap the ICM just in case and bring a spare. I'm not 100% sure this solved my problem, but fingers are crossed. Seems like we're always finding more things broken on the car, and fixing them just creates more problems.

- Josh