1987 454 TBI stalls at idle after a short time

[beady]

I would recommend going back to the voltage/ground check sheet and testing all the grounds.
Here's the checklist in an Excel sheet

Bill, I took all the voltage and ground readings, will post those from my phone in a minute, but I'm posting the winALDL log I took this morning while the truck warmed up and I took readings. It is/was mid-70's outside and the truck was stone cold, not started for days. I think I started the datalog before I startred the truck, and let it run the entire time. After a long while it entered closed loop as seen by O2 readings on winALDL and also by my DVM metering the O2 sensor pin. It seems after it entered closed loop the idle started surging, quite severely, and never stopped. It only filled in one cell of the O2 table, and a couple of the INT and BLM cells.

Mike

 

[beady]

I would recommend going back to the voltage/ground check sheet and testing all the grounds.
Here's the checklist in an Excel sheet

Bill, here are the voltage/ohm readings. The key on, engine off readings were taken cold.

 

[beady]

You must be registered for see images attach

 

[beady]

Video of truck surging at idle in closed loop:

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[beady]

Oh yeah, the O2 sensor ground (pin D6?), was NOT present previously. All the results above, and the surging in closed loop are WITH the ground present. I grounded D6 with a jumper cable. O2 reads now, but o2, blm, and int tables barely register.