Dave WM

the readings you are getting is resistance in ohms. Continuity is a term used in the FSM that maybe confusing, it means there is a low resistance complete circuit. beeping is something the meter will do if the resistance is low enough. the resistance of the oil sending unit varies based on pressure IIRC something between 100 ohms (no pressure) and 30 ohms (high pressure). That is for the oil pressure gauge, and is not the issue for the pump. Since you have a 7 pin AFM the 1st thing to check would be is the micro switch working. Next suspect would be the ignition relay. if those check out the ignition switch could be bad, it sees a lot of use over the life of the car.

you are going to need to systematically address each issue. start with getting the pump running, for this the FSM would be best. But to jump the gun, you need to get a fuel pressure gauge installed, then pull the starter solenoid wire, turn the key to start, while in start the pump should run. if it does note the fuel pressure, should be around 36 psi. This will at least test to see if the pump can run in the most basic mode (start) and that it can produce the required pressure. Next up will be to confirm a spark, for this you will need to replace the solenoid wire, pull the center coil wire, get it close to the chassis ground and crank the engine, this will confirm a spark. Then you will need to confirm the plug firing order. reattach the coil wire, and see if the engine can run on some starting fluid sprayed into the TB, if it runs at all then you will need to see what the pump needs to run, some need AFM input from a micro switch, others need oil pressure, and some may need input from the alternator. All this is so the pump will NOT run if the key is in "ON" but the engine is not actually running, its a safety thing to keep gas from pumping into the engine bay, possibly fueling an engine fire. Its not something you want to bypass. So its going to be up to you to determine what system your setup uses. It may have be altered at some point in the life of the car. Typically you could just look at the AFM and see if it has 5 or 7 leads. If 7 then its AFM controlled, if 5 then the AFM is not controlling it so something else is (does the oil sending unit have to connections or just one). Anyway once the fuel pump is behaving as it should then you need to start looking at fuel control, that would be the ECU and injectors. What you don't want to do is load up the parts cannon and fire, all that does is introduce possible errors in the replacement of parts. there is a process that needs to be followed to sort this out.

since you have had it, did the car ever run?

The above does not sound right at all as far as how your are testing things. You would want to confirm voltage is getting to the CSV by connecting a positive meter lead to the CSV harness and the neg lead to the chassis ground. Nothing to the battery positive. Next you would turn the key to start, look to see if 12 is there only during start. If not try the other side of the harness and test again. This is with the injector unplugged from the harness. Also consider the CSV does not generally activate unless its under 70f or colder. It frequently fails to fire due to the thermotime switch going open from corrosion. Lastly a properly working system will only fire on "start" for a limited number of seconds before it disables itself to avoid flooding (thermo/time).

don't worry about the cold start. Its powered only during "start" and pretty sure its activated by grounding (like the other injectors). You should get a FSM and read the entire fuel injection chapter, read it again... its very through with lots of good info, but will take some time to get thru it.

geez https://www.aliexpress.com/item/32725198406.html fuel level sensor thermistor will get a ton of stuff. Not a big fan of sticking hot electrical items made in china into my gas tank, but I guess even the raw thermistors are MIC as well so guess you have to risk it.

https://www.onlinecomponents.com/amphenol-advanced-sensor-thermometrics/rl200458297d1-51201820.html seems like pretty inexpensive, shipping eats you up.

is that a 4700 or a 270000K guessing 4700 gold tolerance band?

I am guessing anything in the 3000 ohm (tested and works) to 1000 ohm (prob just come on faster) NTC small thermistor would work. The one shown in the pic is prob about 4mm in diamenter and about 1mm wide. You can see the relative size to the canister it fits in. I suspect you want something of the same approximate physical size, not only to insure fitment but maybe it is a way to get somewhere in the correct power/heat/ resistance curve properties as well.

yes easy to do, get the car up, jack stands or ramps, what ever makes you comfortable (or both for security). I found removing the tank mount strap on the passenger side (sender side) gave me enough room to have good access to the retaining ring, and was able to snake it out without removing any hoses or dropping the tank. removing the wheel would be a good idea as well but I did not. You want the car up a pretty fair amount so you have room to maneuver the sendor (and your body while doing that). It may help to undo the fuel pump mount leaving everything hooked up, but I did not have to do that. Really depends on how flexible you are. I suggest you use a grease pin or some other indelible marking to note the orientation of the sender before removing. Its hard to know for sure if you have the sender in at 12 oclock

https://www.amazon.com/Cher9-Values-Thermistor-Temperature-4-7K/dp/B083XSLGXC/ref=sr_1_5?dchild=1&keywords=thermistor+value+pack&qid=1596476471&sr=8-5 think I may pop for this and experiment with the 1, 2, and 3k to see how they behave.

it def was NPT I was able to hold the disk in between the ohm meter probs, got about 1.5k and it would drop when heated. I was not able to resolder the broken piece, I suspect it was a elec weld but not sure about that. Maybe a conductive epoxy. I cleaned it but was unable to get solder to stick. I suspect the material I was "cleaning" was some semi conductor as it sanded very easy leaving what looked like a metallic shiny surface. I am not sure what pure germanium looks like but maybe something like that.

here you go. It seems like there is a meshed liner that acts as a filter for the gasoline that enters the chamber, then you can see the tiny disk shaped thermistor

some items I noted, besides the wide open reading on the thermistor, the slider on the fuel gauge is actually 2 sliding contact points. the one on the WW resistance element AND the one that grounds the slider arm to the metal of the sender. I was having some shaky readings with my analog VOM so I cleaned with some contact cleaner, a little scraping, and then some deoxit and it worked much more smoothy going from around 7 ohms to about 80 ohms full spread. back to the thermistor I tried various contact of the hot lead thinking maybe a corrosion point on the crimp from the wire to the terminal on the sending unit no joy, I cant get any resistance reading even with my HP analog VTVM on the 1 M scale. This makes me think it has to be disconnected as I cant imagine it being that open. another test will be to send a voltage thru it and see if the VTVM can pick that up. I have found this useful when trying to read extremely high resistances. Clearly this high a resistance is not usable but I like to test things before disassembly in an attempt to collect data. doing all this before disassembly just in case its gets destroyed in the process of removal.

yes I will do that, I have a solder sucker and to some solder braid standing by to use.

Oh yes I see that end piece looks like a component of some kind was once there, I did not look at the bottom pic when I made the wire comment. Maybe a glass axial lead type.

hmmm maybe the OE unit is some kind of special NTC resistance wire (if there is such a thing) and not a separate component at all? I assumed it had to be a semiconductor of some kind, but maybe wire that is made with semiconductor material? I will be doing an autopsy of my spare defective unit later and reply back with results.

interesting question, If resale value is your interest, then you need to ask resale today or at some point in the future. Today it would seem early model S30s are the ones that pull in big amounts esp if original. If you use history as a predictor of the future, then you can assume at some point later S30's can be seen the same. So if that is true then originality will be valued and increase resale value. For me I just like things to work as designed, so the challenge is to diagnose and correct the issue. 30 years from now, assuming we can still buy gasoline, an original S30 of any year may bring in big bucks.. or not... I think the S30 is so well designed that its appeal will cross generations. The same can not be said for all collectable vehicles. Some value is attributable to nostalgia, think Model T era cars, or 50's cars like 57 chevy. These cars do not have appeal across generations so I suspect demand will drop as the buyers die off (so will supply of course but since many are garage queens perhaps not as fast). I think for the mid 90s were the high water mark for style of japan sport cars. If I had the space I would look for a very nice mid 90's 300zx. The down side to later models however is maintaining them, as they become more complex, old parts fail and have to be replaced. more parts makes it harder to maintain.

interesting, my OE unit (which was not working) was missing the solder on the bottom, just a hole with a wire coming out that had been bent over. I did not notice any witness marks of old solder. My fix was to solder is so now it looks like the pic above (I presume the solder came off at some point, but hard to believe unless it was poorly soldered in the 1st place). If I have the reason to pull it out again I will prob solder the side to the clip as well to prevent the corrosion from forming there on the ground side as well. Another thing I want to do is to see if I can rotate it to find out how much of an effect orientation has on the gauge reading. This is the side loaded model not the top loader. will have to wait until the gas level drops obviously.

if its not having issues with shifting the sychros (anti baulk rings iirc) are prob ok. You can tell a lot after its apart. there are specs for how to tell, and you can test by seeing how well the "grab" and lock onto the cones of the gears. Reverse is not like the others, its not constantly meshed. It relies on the shape of the teeth to allow it to mesh with the reverse idler, so every now and then you could have those two gears line up perfectly tooth to tooth, will not engage. just ease off the clutch in N and try again.

Yep bearing cage for sure. Rebuilding is not that hard to do, helps to have a press and some pullers but as EuroD mentioned may as well open and examine before buying a kit. I am always amazed at stories like this, trans works even with all the carnage in the case. I guess the bits tend to fall down and not enough wave action to drag them up into the gears. As long as the balls have stayed inside the bearing races it seems damage does not happen.

here is one for you "come on bobby pin....pop"

Miss fuzzy britches..

reminds me of the old joke Comedians get together every year for a convention. after years of telling and retelling the same old jokes they start numbering them for convivence. guy gets up on the stage... says into the microphone #26... a few giggles....#104....some more....then #62... uproar!!! a guy in the crowd says, "man that was a good one" guy next to him says yea, but what about the great timing....

city on the edge of tomorrow (oops forever)..like the use of vacuum tubes.. an accident with a mechanical rice picker.... CO and I spent WAY too much time in front of the idiot box.