Everything seemed to be working very well until yesterday...
It was threatening rain so I left the top up and tried driving home with the A/C on. My solid car became a tempermental fucktard.
Whereas previously my IDLE PWM to maintain 1k RPM was about 37% with fans, headlights, and even A/C, I was having problems with the car dying unless idle PWM was 58%. (that same PWM value on my drive to work this morning sans A/C and with much lower temperatures caused my RPMs to be about 2,500)
Battery voltage indicated in my logs hovered somewhere around 11.8 until I got to about 3k rpms at which point my indicated voltage would hover around 14v.
Also as a symptom, it seems that my 3,500rpm and lower and 65kpa and lower cells on my VE table seem to be ping-ponging up and down every time I drive. My high RPM high load cells never change more than a tenth. Low RPM low load cells require a higher VE number to hit the same pulse width which may explain it but I still am confused as to why.
Here are a couple givens in my car:
NB alternator controlled by stock ECU (for now).
Battery is getting a little old perhaps.
When Megasquirt indicates 14.4v, the voltage indicated on my DC/AC inverter reads 13.6-13.8v.
My ideas on what is causing this are:
Has anyone messed around with the new Alternator control in the latest alphas/betas?
I have an NB alternator control circuit that I never installed. Am I better off using the hardware board or messing around with software? Do I have to make any modifications to the board in order to do it with software? Anyone have any fast and easy settings for an NB?
Is the best way to test the battery just to take it to an auto parts store? What is your favorite replacement battery?
Next, grounds. I see that most of the stuff that seems to be contributing to my issues is grounded at the same point, JC-02. Anyone have any first hand idea of where to find it? I hear it may be UNDER the headlight.
Any other ideas? I will upload some logs when I can isolate stuff that is interesting. Sorry for the wall of text. Any questions I can answer?