So I had the Red Shift Orange car at MSR Houston in an HPDE this past weekend for a shake down. The car was recently re-wired to try and chase down electrical gremlins that have been plaguing it for years. I think all the issues have been sorted and the new harness has exposed the root of the problem.

In the 30 minutes the car ran on track (for the whole weekend, pretty pathetic) she munched 2.5 Ignition Coil Modules (ICMs). One was a GM ICM, the other two were Auto zone specials. Short of swapping the ICM in the middle of each session I'm at a loss of how to fix the issue. When she was running, she was the fastest thing on the track (if you exclude the two Z06 vetts).

I put a cheap-O oscilloscope on the 12V bus of the car this evening, and noticed that with the car running or off, the alternator seems to generating some high frequency noise (roughly +/- 1V @ 1.5kHz). There is always some measurement uncertainty, especially since a good scope costs more than the whole car. Verified the electrical noise is coming from the alternator by disconnecting the coil exciter line on the back of the alternator.

I swapped the alternator with a new reman unit, no change in measurements.

Other symptoms:
- There is a low hum coming from the alternator when the engine is not running. I suspect it's there when the engine is running, but no way to hear it.
- The tach needle is erratic at idle and fine above idle. I'm thinking this is indicative of electrical noise.

I have a 470 ohm 1 watt resistor on the exciter line (I think it's L on the plug). Alternator is charging beautifully @ 14.5V

Not sure where to go from here. I'll probably try swapping a third alternator into the car out of desperation. Hoping to run TWS comp school, not sure how well it'll go unless I bring ~20 ICMs to the track.

Thoughts?
- Josh