88 Toyota EFI - reading more than than flashes?

I like a challenge I guess.
I have this 22re efi that started acting up last winter on a drive over the mountains (40 mi).
The first symptom was dying when I came to the first stop.
Didn't want to run at low rpms. Ok once above 30 or so.
I've gone through the FSM diagnostic procedure multiple times now and swapped parts to boot but still no joy.
Searching the net for DIY solutions has not proven fruitful as my ECU does not have the T2 pin on the ECU.

But I do have an old (70's ?) oscilloscope and the Schematic.
Do I know how to use it?
No, but I have in the past, as the hands for my Uncle who'd had a stroke.
And after starting the process of learning about Data Era cars I have a better grasp of what's going on and, I like to learn new stuff.

If I can locate the circuits via the schematic and log the KOEO data would that shed any more light on whats going on?

I will say I have not proceeded into the next FSM diag step yet, which is Testing the ECU.

Just so I understand this car doesn't idle? Does it run real rough when low rpms or just stall as if the engine was turned off ? You say ok once above 30 I assume you mean mph? If your in park (or neutral) what rpm does it take for it to run good? I don't think the oscilloscope will be necessary for this repair, well see which direction we need to go with a little more info into the problem. What parts were changed for this problem?

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Thanks Ben

The first post described the original conditions/symptoms
It has remained in that basic state.
Its been suggested I'm experiencing "Limp Home Mode"

So It has a new TPS , Plug wires, Plugs, air filter(jeez this sounds familiar)
The FP, Temp, Circuit control solenoid all test @ spec.

Last week I needed to jump the Buick and used this rig, it's been sitting for several months.
fired up ran smooth and revved up sitting in park just fine. I was still in (personal test) Open Loop . (trying to get these terms right in my mind)
I Needed to jump a while and observed the thing idled for 20-30 mins no problem.
Try and drive and it cut out.

While doing testing the day before yesterday I noticed it idle with a distinct On/Off cycle of "something" that raised and lowered RPM but it didn't die. Wasn't what I would call a Surge but similar. More abrupt.

Received the new O2 sensor and installed it today and now... it won't stay running more than a second.
Fires immediately but dies.
I feel I am improving at making thing worse however.

Glad the scope can stay in its box under the bench for now.

How many wires does this sensor have?Check the pins on the new sensor vs the old sensor .. an 02 sensor shouldn't have that affect on an engine on first start .? Are you able to keep it running by pushing the gas pedal?

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Here's the old one

The readings I got from this ECU check in the FSM.

After days of tracing connections and checking the Resistance per the FSM I'm back where I starterd only now I have 2 codes.
A #21 which says O2

and #31 Mas Air

I have one test for checking the signal from ECU to O2 left to preform, but I have 2 digital DMOV and the test is to read how many times in ten seconds the needle bounces.

If I knew more I'd hook up the 2 channel Oscilloscope and get this reading but so far all I'm getting is the scope trigger signal from what I can tell.

I could post the FSM O2 flow chart, schematic and check lists readings I have if that would help.

I'm really trying to make the process of checking things thoroughly before buying a new ECU work.
but this last test is kicking my butt.

What I'm working off/with

Sorry I've been away for a while . Where are you at currently does the car still die immediately after starting ? The oxygen sensor doesn't have that much control that quick ,the maf however certainly could cause that. I'm not sure if this car has a backup strategy for the maf if you were to disconnect it or not but it's worth a try. Also I see stj-e1 and ne-e1 isn't within spec what are those components?

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Well I ordered a 1008 hantek which will arrive Wed and a new ECU a few days later I think.

I spent half a day driving around looking for a new analog DVOM or is that AVOM?
No success. Came home and rehabbed an old (1950s?) meter enough to get the signal I needed... No signal.
That's when I ordered the ECU.
The flow chart and my frustrations all seemed to align in that moment.

STA looks to be the ecu to ign switch/ecu pin of the Circuit Opening relay
NE is a leg for the Igniter its part of Igt,Igf,NE
STJ is cold start injector

Still won't stay running more than a few sec at most.

I ran through the Mass air check list and checked wire continuity but all those passed in spec

Curious as to where this left off.