Hondata

I've been tuning my fuel maps for the past month and I realized that when I tune the car at night it runs different than in the day, I took a closer look at my readings and found out that it's not that it's night or day, it's the power draw from my battery with my headlights.

Is there a way to make it so my headlights drawing off the battery dosn't adjust my AFR? it seems to run richer with the headlights on by about .2-.3 AFR.

What is the voltage at idle with the headlights off?

What is the voltage at idle wiht the headlights on?

which voltage? battery? ELD?

battery voltage

with nothing on, period, I get 14.00-14.05 V
with just the headlights on I get 13.85-13.90 V

I think you have found the problem. Your battery voltage should be pretty much the same with lights on or off. The voltage may drop for a second or 2, but will go right back to where it was.

Where are you getting you power and ground?

I recommend getting power from the ACC ON power source on the fuse box...this is a switched 12 volt power source. Any good solid chassis ground will work.

do you think it would be a good idea to buy a transistor voltage regulator tuned to 12VDC and put it in series with my current power source?

A voltage regulator should not make any difference, as the wideband will have internal regulation, but you could try it.

You could also try switching on electrical load (headlights + heated rear window + fan on full) and see if the AF ratio changes.

is electrical load going to work? I'm using the ELD line into the ECU for my AFR.