having a hell of a time diagnosing this

Ok...
1993 Cutlass Ciera 3.3 3 speed automatic.

A while ago it starts running rough while driving and under load.
I do a fuel pressure test, and it comes back to 30-32 PSI. Low. Install my return line shut off tool. No change. Bad pump.

Change pump. Change pick up screen and fuel filter.
Now has mostly smooth idle, still issues under load in the mid range RPM band.
Check the PSI again, 36, raises to 41/42 under RPM revving. Base pressure still a tad low so I install the block off again and can easily get 60+ PSI.

Changed the fuel pressure regulator.
Same issues, no change. Also same pressures. Remove the throttle body. Clean the TB. Remove the IAC. Clean the IAC and the IAC passages. Remove the MAF housing and the MAF sensor. Clean and dry the screen, reinstall sensor and housing.
No change.

Ohm the wires, front side all under 9 back side all under 13. Plugs look fine, slight red traces, nothing major and clean tips.

Ohm the coil packs, all floating around 5.8-5.9 on the secondary. none above 9.6-9.7 on the primary.
Pull the ICM and test it, run the heat sink up until I could not hold it anymore. Every test tested good. Did the same two days later, same results.

Removing the plug wires one at a time all reveals the same RPM drop on each plug, so the issue I would think is not ignition related.

I have not ohm'd the injectors yet, simply because I cannot find any sort of spec as to what they should ohm out at.
I also cannot find an auto parts store that can get me a simple injector pig tail so that I can pull them, hook 9V to them to open them and blow them out with air to check patterns.
The junk yards will not allow to simply get a pig tail from a car cause they want to sell the precious harness in one piece.

What else am I missing?
Before just simply tapping the key it would start, now it takes several tries.
I drove it the other day and noticed that now suddenly the speedometer is not working also.

Also forgot getting no trouble codes at all. Just 12.

AllData has simply run out of options for me cause I do not have an injector flow bench, or the flow balance tool (and I am not spending $800 for the complete one either).

I think I have listed everything I have done or thought of.... who knows. Ask and I will answer, advise and I will check and test. Solve and be promoted to saint.

What exactly is the symptom you are trying to get rid of?

The injector pigtails are available at the local NAPA for about 13 dollars.

What exactly is the symptom you are trying to get rid of?

The injector pigtails are available at the local NAPA for about 13 dollars.

Right now it has hesitation in the mid range RPM band that prevents it from being able to be driven reliably. And most time multiple tries to start.
Upon occasion when you slow down or come to a stop it will stall out and die.

Does the brake pedal seem harder than usual to apply?

Does the brake pedal seem harder than usual to apply?
not particularly.

Apparently the few people I talked to at autozone were just complete and total idiots. No surprise there.
I had called NAPA but they wanted 25 bucks for the pig tail.
I went to crap err autozone and looked the damn thing up myself and they had them for 9 bucks.
I am going to get three of them.
I also ordered a ultrasonic cleaner and will get some nice mineral spirits, or that chem dip stuff.
I will wire power to the injectors, hold them open, and give them a nice soak and see what happens.

The only other thing that I checked was the engine is only pulling 15-16 in of vacuum at idle, but changes with RPM nicely. I do not hear any leaks anywhere. Just another possible piece to this screwed up puzzle. Though at 469 or whatever feet it would be a little higher than that, closer to 17-18...

I am really hoping that the injector baths solve this. They are the only other real things left untested. Though to just go like that... maybe the pump pushed some crap through before it got replaced and clogged a inlet filter to one or more of them...
Just the fuel out of the fuel filter was clean, both sides.

well thought would update this.
The problem was that 'new coil' that even tested with-in spec.
I kept looking at the old one thinking oh what the hell swap it back in.
Fired right up, ran fine.
Those loud 'clunk' noises went away, it idled and revved up fine with little to no hesitation. It still has a very slight hesitation under a 3/4-full pedal take off but I think that is just the injectors needing a cleaning. Which I have a 1.5 liter sonic cleaner on the way for that.

While I have seemed to solve the running issues, now the speedo has decided to quit working.

With the car up on stands, and in Drive, the speedo output from the ECM C2 plug, wire B11(drkgrn/wht) I can get 9 volts with the brakes on. When I release the brakes, and the tires start to spin it raises very little, I think the highest it went was 9.2 something. Even though I was in second gear.

According to the wiring scematics, this should have been the direct buffered output from the VSS input. Since it does not really seem to have much variation in the signal am I looking for a VSS or something else?

I already checked the VSS plug, and even unhooked it and re clipped it in to see if it was a bad seat.

The only thing that has been going on in that area of the car was I recently replaced the PS pump, and I am not sure if any got on the VSS housing or not. Thoug since it was weatherpack connector I do not think that it would be an issue.