Been scratching my head on this for awhile, finally thought I would pose my issue to this group for some assistance. I have a TBI system installed on a 78 Corvette, powered by a 16197427 PCM. Been running great the last few years. Past couple months, I noticed some serious stumbling once the car heated up. Turned out my coil had come loose from its riveted mount and was causing lots of problems. Swapping in a good used coil made it run 10x better.
I had it hooked into TunerPro and noticed it was not entering closed loop. Sometimes the flag would turn very briefly to Closed, then the next moment back to Open. I watched the oxygen sensor readout and it looked really, really slow. Knowing that the PCM was looking for an O2 reading as part of the parameters to enter Closed Loop, I purchased another (Bosch 13077) and installed today. Took it on a 10 minute test drive and it still did not enter Closed Loop.
Can anyone list the parameters for closed loop operation? I know that Coolant Temp must be at a certain threshold and run time. Is there something I'm missing?
Attached is the current .bin file that the car is using, I'd greatly appreciate any comments and thoughts.
Thanks!
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