This is on a 92 RS 305 TBI car. I recently put some headers on my car and the air system was removed, EGR valve is still in place. I temporarily didn't install an O2 sensor. Immediately it was pulling up a check engine light. After about a week of driving it would intermittently stall out, but start right back up. Then today it decided not to start again. Eventually I got it started and to work.

Checked the codes and it was pulling up 13 (O2 circuit) and 23 (M/C circuit?). O2 was installed, still stalled though. Reset computer and it made it home without stalling out (it was stalling very badly previously).

However it is still pulling up a code 23. I cannot figure out what this is? It has something to do with the fuel sysem and best I can find its a mixture control on a carbed car? So this would be reverting to my Idle Air Control Valve I assume? Any advice on what to hunt for and more information on what this code is would be helpful. Or do I just have to flash my computer and reprogram it to run with headers and w/o an air system? Thats the best I can think? There were NO problems with this previous to my dumb self fixing something that wasn't broke