Zed Head

You can see in your picture that the sleeve is narrower than the polyurethane bushing. People often just sand down the PU. But, as cgsheen1 implies, you can just compress the PU and squeeze it in there. It's elastic. Don't sand down any of the metal parts, it's only the PU that's a problem. I've used a thin paint scraper with lube on it to wedge the front bushings in to place. Use the thin piece of metal as a lubricated ramp to get over those edges. Once you get the edges started just squish it in there.

That is odd. In order to create a spark the circuit through the coil needs to be completed then broken. It looks like the circuit is being "made" then being broken, maybe just due to overheating. I'm going to guess that your ignition module or the ignition coil is bad. When you turn the key on power flows through the ignition coil and the ignition module, something inside the module or the coil overheats and the circuit is broken, and a spark is created. It probably happens on #4 because the rotor just coincidentally was pointed at the #4 terminal in the cap. If you turn the rotor to a different spark plug you might get that plug to spark the same way. Feel free, anyone, to critique my guess. Since you already identified the coil as being out of spec. that's the easiest and cheapest part to try. If you have a spare coil of any type it will probably work for a test. If you want to try the GM HEI module there are some writeups on the site. It's just four wires and a place to bolt it to a good ground.

One of the bearings in the transmission is known for making noise. I think it's the countershaft bearing. Doesn't hurt anything it's just annoying. There are stories of replacing the bearing with a new one and have ing the nosie come back within a very short time. Might be why Nissan went to a bigger bearing with the 71C transmission. What kind of "some noise" is it?

Now, on top of it all, we have the "Wuhan" hornet... C'mon! https://www.theguardian.com/environment/2020/may/02/murder-hornets-washington-state-bees-twitter

You should hear all six injectors click at the same time. It's very hearable when the engine is not running or the starter turning. It might be that your ignition system needs some work. I think that you said it used to start then die, now it doesn't start at all? Maybe recheck spark, then tune the ignition system if it's gone. Do you still have the original ignition module? It might be that it is dying also. 75 was only the second year of electronic ignition and the modules are very old now. You're pretty close I think. Reconfirm what used to be. If you have lost spark there are some cheap and easy ways to upgrade to a better more powerful ignition system using a GM HEI module. That module also got rid of the tachometer issue on my car. Stronger spark and no injection problems.

Sand, verb. Or grind.

Actually, you're way ahead of most people new to EFI (no offense to most people). You have a meter, you're using it, and you're getting real numbers. 1975 was the first year of EFI so Nissan's book wasn't the greatest. Here's a later one that has tests for all of the years up to 1980, and has better numbers, than "small resistance". You have to pick through and find your year but they give more info. Your 185 would be about 150 in the newer book. Close enough I think. I would focus on the Pin 1 signal. Is the tachometer still in the car? I've found that the whole circuit from the coil to Pin 1 needs to be intact for the ECU to open the injectors. Sometimes the system own't work if the tach is disconnected. There is a simple trick for checking the Pin 1 circuit that lets the ECU know when to open the injectors. Connect a wire to the coil's negative terminal. Turn on the key. Tap the other end of the extra wire to ground. You'll get a small spark as the coil circuit grounds. Every third tap should cause the injectors to click. That's what the ECU does, it counts sparks then injects.

Resizing the bushing is pretty common. Some people manage to wedge them in there with some lube and some trickery. Here's one thread that mentions it. It starts out on the other end, loose, but ends up at tight. There are other posts about the issue on the site, try some search words in the box at the top of the page.

Here's another. https://www.youtube.com/channel/UClvow1RFSyeh5CRwRB_m5sA

Just wait... Edit - I overlooked the first part of your comment. You're forgetting, maybe, about The Wall. Defense money was moved over to finance a few extra miles. "Emergency declaration" I think is the key phrase. https://www.vox.com/2020/1/14/21065352/trump-diverting-military-funds-border-wall-construction

Sports fans, soccer. There's probably others. NBC has a bunch of condensed and classic matches for free.

https://www.thezstore.com/page/TZS/PROD/11-3450

Check resistance at the sensor itself. They don't really go bad often. Many get replaced for no reason. There are some bullet connectors in the harness between the ECU and the sensor that can come apart. The sensor is the small one with the injector-type connector, not the big one. The big one is the thermotime switch. They're both on the thermostat housing. You might pull a spark plug and see if it's gas-fouled. All of these small things add up. Keep knocking them down.

Seems fitting somehow. Pointless expensive military shows falling apart. https://www.nola.com/news/article_c2c9fb8c-8be6-11ea-a01c-03e9ac7cb93d.html

Shanghai'ed. https://www.theguardian.com/environment/2020/apr/30/no-end-in-sight-100000-crew-on-cruise-ships-stranded-at-sea-coronavirus

There's no good reason for only one injector to lose power at the ECU connector. Power comes through the harness to the dropping resistors then through the injectors to the ECU connector. Could be a bad injector. Might explain the rough running. But the engine should keep running on five. Check the coolant (water) temperature circuit at the ECU connector, using the book as a guide. It might be that it's disconnected and the engine is flooding. If that sensor is bad or disconnected the ECU will add a lot of extra fuel. Like you're in the Arctic.

Are you sure that the EFI harness wires are connected at the battery? They have plastic connectors and connect to the negative and positive posts. Don't get them mixed up. Check your fusible link connections. They get corroded and can lose continuity. I think that there are two under a single plastic cover on 1975s, plus the one in the wire to the positive terminal. Using your meter is the way to go though. Make sure you have power where it should be and check grounds also. Keep a list and record the actual numbers that you get. Something will show up. Most people with EFI have been where you are now.

There are easier things to do before taking the injectors out. Most of your troubleshooting is electrical on the EFI system. You can check the injector opening signal with test lights.

This should work. A Sawzall with a metal blade should cut through the sleeves and bolt in a minute. If you set the bushing up in a vice with some preload the heating method works really well. It will move as soon as the bond breaks, so you get minimum smoky rubber vapors. My spindle in was seized to the inner sleeve in the back. Took a while to realize it. It happens.

Despite the variation it ended up with the ubiquitous pseudo-wool seat covering. Some company made a killing on that fake sheep skin.

I wonder if this wood-focused powder would work? Wuud. https://www.alphacoatingtech.com/mdf-powder/

What year is it? Could be the fuel pump switch in the AFM. Or you might be starting on the cold start valve but not getting injection from the injectors. Seems like you're looking at the right things. Are all of the hoses intact on the engine? PCV, valve cover, AFM, etc. Is the AFM plugged in? The plug has been known to fall off during assembly if you've removed it. Many possibilities. Give us some details on the car and engine.

That is actually a good analysis, I think. The valving should hold a vacuum, it's essentially a check valve, preventing the fuel from exiting the filter and lines because no air can get in to replace it. Like when you pull soda from a glass in a straw by holding your finger over the end of the straw. You might be able to cobble up a fix for the leaky valves with a real check valve between the filter and the pump. Ideally the pump would work correctly but that's life in aftermarket world.

Look at the wear patterns on his rocker arm pads. Most are way off the end. There was a guy a couple of years ago that had a similar pattern, and noise, and you could see wear on the rocker arms, completely off the end of the pads.

Just saw one of this guy's videos on tv. He's a sports commentator with too much time now. He has dogs. He has a few of them.