Chances are that sensor for the low fuel warning light is probably past its prime. Definitely worth a shot. Nothing to loose by all means.

Welp, gave evaporust a shot and I was pleasantly surprised. It clean up quite nicely.

Now I just need to grab the multi meter and see if all still works.

Not sure of the procedure to test the low fuel sensor.

I was working on replacing the battery cables and I noticed that one terminals on the fusible links had come loose from the link, so I decided to order some. I got them from Zcar depot.

Im going to replace the black one as well and I was hoping someone could tell me the wire gauge for the small white chuck of wire. Also there is a butt connector in the middle of link, Im assuming it blew and someone just put it back together? The butt connector looks like its been there a long time.

Also, I have a new green link, im not sure where that one goes.

This might help. Thanks to Blue 246.

https://www.atlanticz.ca/zclub/techtips/fusiblelinks/index.html

Im not certain that those links are correct, but i could be wrong. The post mentions that he has not verified and I can find mentions in the FSM but no sizes.

These are the original wires

I've also ran into an issue getting the injectors to fire. I think this is the last piece of the puzzle to getting the car started. I followed the FSM and the Fuel Injection manual and I cant seem to get continuity to pin 20 of the ecm. After hours of tinkering, I think this problem is above my skill level. I've contacted a local classic car repair shop and I'll have them look at it in a couple weeks. Im curious what people are doing for an upgrades. I wouldnt be surprised if I need injectors. Seems like there are other options besides stock.

I will describe this as if you are using Nissan fusible links.

You should have a black fusible link (https://zcardepot.com/collections/electrical/products/fusible-link-wire-black-280z-75-78?variant=49681656086840) connecting the white wires. You should have a green fusible link (https://zcardepot.com/collections/electrical/products/fusible-link-wire-black-280z-75-78?variant=49681663656248) connecting the white/red wires.

The black fusible link is for main power. The green fusible link is for the ammeter.

What exactly do you mean by "I cant seem to get continuity to pin 20 of the ecm"? Continuity with what? What test are you running? What page in the FSM?

I bought the kit from Zcar, (https://zcardepot.com/products/fusible-link-wire-set-280z-75-76?_pos=3&_sid=8d8163666&_ss=r#)

As far as troubleshooting, I started with page 33 of the Fuel injection book, which then points me to page 55 for the continuity test to ground for pin 20.

If that fails, it points me to EF-33 of the FSM which basically tests the relay. The relay tested good. At that point I just started to get really confused

So, from how the circuit is wired, saying pin 20 should have continuity with ground appears to be an error. This is based on the assumption that you are still working on a 75 with the corresponding control unit.

Pin 72 is ground. There is a resistor and relay coil between pin 20 and pin 72.

In addition, pin 20 & pin 36 are connected at the EFI relay. Pin 36 goes back to the AFM. It gets 12VDC+ when the key is on and the AFM flap is open. This operates the relay coil to run the fuel pump. From my research pin 20 is to indicate engine running.

This site gives a good accounting of the pinouts from a BMW site: https://www.firstfives.org/faq/ljet/ecu_pinout.html

I also attached a PDF of the file.

L-Jet ECU Pinout.pdf

So, im shifting gears for a moment to mess with the ignition again. The current setup that I had ran through the ballast resistor. I had spark, but I felt that it was weak so I opted to upgrade to the MSD Blaster coil and Pertronix Ingition module so that could bypass the ballast. I've got it hooked up and getting spark, but its no better than it was before. Maybe Im wrong about what the spark should look like and all is fine. I dont know.

The posts and diagrams that I have been able to fine are either for the 240 or the 280 with a different ballast resistor. I just want to double check and see if I need to do anything with the rest of the wiring attached to the ballast.

On another note. Does anyone have a line on where I can get an original TIU. Or is Ebay my only option.

There are two Pertronix Ignitors out there, I think, that will work with the Z distributors. One requires the ballast resistor or it might get damaged, the other has more modern current control.

On the TIU, you can make any of them from 1975 to 1978 work if you don't use the second pickup coil in the distributor. I'd find a 78 version if I wanted to be close to original.

But, really, I'd use the stock distributor and pickup coil with a GM HEI module. A modern ignition unit that's cheap and widely available. Might have been mentioned in a past post in your thread. Not sure.

When you're optimizing your wiring, remember that there are two basic parts of the system - the triggering portion and the coil current portion. The strength of spark depends a lot on the coil current. You need full positive power and a solid path to ground. The path to ground is through the ignition module body, sometimes, which passes through the distributor body in the Pertronix application since it's mounted in the cap. The distributor has to have a good ground path so that the Pertronix module has a good ground. That's actually true for points also.

Lots of options. Does it run yet?

Edited May 2May 2 by Zed Head

It doesnt run at the moment. I cant get the injectors to fire and I think that problem is over my head so im sending it to a classic car repair shop on thursday. I've basically been putting the car back together and cleaning up. Im probably going to have them replace the spare tire pan and give me an estimate on floor pans. I cant put the fuel tank back in until the spare tire area is fixed since the mounting point is rusted out.

Im hoping the injectors are the last bit of the puzzle to getting it running. Then its a matter of make it run well. Ideally, it would be nice if I could drive it home lol. We'll see.

This was the igniter I bough

https://www.amazon.com/dp/B000CCFK5Q?ref=ppx_yo2ov_dt_b_fed_asin_title