Still kicking around a 013 code

[Y-JobFan]

Been dealing with a 013 code on my 90 Coupe which we know is O2 sensor fault. I have tried 2 new sensors, it has a new MAF sensor, new IAC, newer spark plugs and wires, new air filter, have checked vacuum lines. Also has new Delphi ICM and new Delco coils. Car runs rich, fumey, and tends to surge some when sitting at stop lights or tooling around where you don't really need to be giving it gas, and gas mileage is down. Check engine light comes on for it intermittently.  Runs down the highway beautifully but does have a stumble out of the blue on occassion which I feel has to be tied in as well.  What other items could be suspect ?  The light has been showing up more and for longer periods recently also 

 

[2seater]

I can only offer this possibility: we were resurrecting an ‘89 for my grandson last year. It had a number of gremlins and one of them was an O2 sensor issue. We had a clue there was something long term going on there as the car came with a small notebook that roughly listed the items serviced over the last few owners. We noted the O2 sensor was replaced several times so two of us traced the sensor wire back to the ecm. We then connected a ohmmeter to the two ends of the wire which appeared to have continuity so we simply disconnected the appropriate plug on the ecm, sprayed with contact cleaner and plugged and unplugged a couple of times. The O2 problem went away so a poor connection was the likely problem, but later we swapped ECM’s for a different reason so I am not certain about the cure over the long haul

[padgett]

What are the O2 ED07 and Transitions ED18 reading when closed loop is reached.