So I was driving back from the bank and my 1991 80 series just stopped running. I started checking the usual suspects EFI relay, fusible link, battery cables. None of that made since because I still had CEL. Waited 5 minutes and cranked and it started. I parked it at the house and now it won't start again. I checked the codes on it and got 4 different ones. 14,24,28, and 31... This is pointing towards AFM and Igniter and the O2....my question is what do I start with? Any ideas. Do I just find a used Igniter and AFM or is there some steps to go through first??