So after a little more time observing the LTFT, I've found that it seems to get worse the more filled the gas tank is. This week I was on about a quarter tank or less and the LTFT were doing surprisingly well, although still well into the negative. I did a fill up and then went into a drivethrough, and after idling for a few minutes I noticed my LTFT was between -22 and -25 (seems that -25 is LTFT's max), and this isn't the first time I've noticed this happening. I've ordered a new EVAP purge solenoid and we'll see if that makes a difference.
I tried putting my original PCM back in, but even though I tried reconnecting the connections multiple times it wouldn't work, might've been damaged from when I had it in my trunk for a little while. The LTFT issue was still present on the stock one anyways.
As for the P0300, it's mostly (pretty much only) on cyl 4, and only when started 15-50 minutes after a fully warmed up drive. I switched from AL104's to 605's and it made it a bit better again. I've tried doing the CASE learn on my Aeroforce Interceptor many times but cant seem to get it to work. Been considering popping off the rear valve cover and checking the stiffness of the lifters on cyl 4 through the rockers.
P0703 has been gone for weeks now.
