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Ya. I tried 3 different brands and returned them. Only the one that came with the car would start right up and run. So, Its gotta be caused by something else. If these couple new sensors don't do the trick, I feel I may be looking more towards the ECM again. Nothing is making much sense yet.

Ah okay. Good to know this is you on the forum end.

I don't want to muddy the discussion but has anyone noticed some similarity in the rpm bands that show up as misfires, vibrations, poor running and other observed problems? I don't know what that means, if anything. At 1500 rpm and three power pulses per revolution, it works out to 75Hz. I have no theory if there is a harmonic that manifests itself? I have a rattling heat shield on another car that only does so in a narrow rpm band, so it got me to thinking??

There aren't any hard numbers that I know of just general trends I have seen from years of fooling around with these engines. Warm idle timing around 20deg, a couple degrees more when idling in gear to pick up the load. Timing should advance some as rpms increase. I was looking for a substantially low timing in the problem zone. The pulse width is simply the amount of time the injectors are open, so much like the timing, I was looking for a radical change. That said, if the engine is warm, the pulse width should be pretty steady at a constant rpm. Also, it is dependent on engine load. Because this injection system is timed, the injector open number is for each cycle and isn't a steadily increasing number. If the pulse width is unstable at a constant rpm and load, that does not sound normal? Is the readout indicating closed loop? Warm engine, 900 and 1500 rpm points should have the O2 moving around above (rich) and below(lean) ~.450mv Again, there is no hard number but more cross count is better. Zero isn't good but the conditions to get the O2 hot and active must be met as well.

This might be a silly question, but have you checked your standard auto parts stores? I replaced the ICM/Coils on my 88 using brand new Standard Brand parts purchased from O’Reillys. Plug and play parts, exact gif and setup as originals. Worked first try. Part numbers are STD LX349 and STD DR36

Have you tried connecting a fuel pressure gauge to the fuel rail and watched what it does when the engine starts jumping a sputtering. If not, you should.

I have done quite a bit of work on the brakes since my initial pump/accumulator replacement and suspect their may be some residual air in the system. Im gonna bleed it all again and see if its an issue. I didn't notice if the UART was still there. It was a history code too, which could have been a result of unplugging a few sensors. Think @Ronnie had mentioned the temp sensor, which was acting fishy, so I ordered that and a throttle position sensor... as when I last had it running, the idle would rise to about 1200 rpms for a sec and drop back down. I have the new emissions purge valve to install as well. I figure knock out these suspicions and see where we're at at that point. So far, every sensor ive replaced has contributed to a better running engine. Parts won't arrive till after the 14th. So I'll probably work on the back bumper paint job till then... and make a new video with an update.