So I've been battling a p0620 and erratic "check charging system" errors. I had replaced the alternator, the pigtail, and even ran a new wire to the PCM. Using my scan tools (Handheld scanner, and ELM327 with torque pro), when this would happen, the PCM would sense 9.0v or 22.0v - Probing the wire at the PCM would yield 13.5v, as would probing the battery, so the alternator was obviously not the culprit here. I was just ignoring this for the time being until I could do further troubleshooting before popping 200+ on a reman PCM - However, yesterday I was driving back from somewhere and went to pass someone and experienced a misfire and a huge power loss. I pulled codes and got a P0316, P0303, and P0620. At first I assumed a coil had failed, but this was running much, much worse than just a single cylinder misfire, it almost sounded like it had jumped timing (It hasn't. If you turn the car off and on it runs fine for a couple of seconds). I cleared the codes and then re-pulled them immediately and got a long laundry list of codes that were completely different than the previous set (See picture). Codes were : P0300 (Random misfire), P0307 (Cyl 7 Misfire), P0308 (Cyl 8 Misfire), P0316 (Misfire detected at startup) - This code set itself without ever experiencing a start cycle, P2196 (02 Bank 1 Sensor 1 stuck rich) , P2197 (O2 Bank 2 sensor 1 Sensor Signal stuck lean), P0620 (Generator circuit fault), and P1000 (This code has always been there recently, even after all readiness monitors are completed.) I also noticed the MAF voltage was reporting 1.3-1.6v at idle, which is super high. It was too cold out last night for me to probe it with a multimeter, but when I disconnected it and started it , it did the same things in Fail-Safe mode. Idles perfect and continues to degrade the longer it runs. I can't imagine all this failed at once, but i'd hate to waste 200+ on a computer to find out it's something else. I've checked the harnesses for any damage, haven't found any. Just wanted to post here to see if anyone had any ideas before I pop for a PCM. Thanks!