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If you do get the engine running well, replace all of the old fuel lines on the rail and the injectors before too much driving. I smelled gasoline on mine one day while driving and when I opened the hood a tiny stream of gasoline shot by me on to the sidewalk. They dry out and crack lengthwise. The small stuff will eat up a lot of your time but it's worth it once you're done.

Here is a way to test the function of the injectors separately from the ECU. With the ECU connector removed from the ECU, turn the key on. Then short the pins in the ECU connector from the injectors to ground with a quick tap. Each tap should produce a click frm the relevant injector. You'll need a quiet garage or a friend in the engine bay to hear them. Or a long wire.

I believe he mentioned 10 plus years.

That makes sense, I already testedt all the ECU pins and were reading correctly... The only thing left is the AFM which would also make sense why the injectors wouldnt firing. I tested each injector and they are functioning. I have stopped testing for the night because i broke a fuel line that was very old. will need to replace that before messing with the AFM. but i dont think im getting good signal from the AFM to the ecu. thank you for your help everyone.

How long has it been sitting? What's the back story?

I’ve mentioned it some many times in the past about replacing each and every connector on the EFI harness and cleaning each connection in that arena. You will be amazed at the corrosion that you find on each connector and the wire itself. I had to shorten some wire by over an inch before I could find wiring that was suitable to crimp/solder.

The engine can run off puddled fuel in the intake manifold. If the injectors were opening the engine would continue to run. cgcheen's suggestion about testing with a 9 volt battery was a good one. You can run separate jumper wires if you don't have an EV1 connector. With a 9 volt alkaline battery you don't have to worry about melting wires if you accidentally short them. You'll hear a click when you connect the 9 volts, if they're opening. Also, with 9 volts you can leave the voltage connected while you tap them. You'll have the solenoid pulling them open if you can get them to break loose. Pin 1 at the ECU is the ignition signal that the ECU uses to monitor engine RPM. It's connected to the negative terminal of the coil. It should read battery voltage with the key on. But it also needs a certain type of voltage pulse. There are things that can screw it up. You're making great progress.

I almost made a comment about AI. It's basically a better Google search. But that's about it.

I am reading through the FSM and all the materials trying to track down what i can find. Using AI is extremely helpfull as it walkthrough alot of troubleshooting and ruling things out. Right now i believe ive rules out the fuel system, the injectors are all functioning and sensors because its stopping after a running for ~9 seconds regardless of its tempature, hot or cold. The last thing for the ECU troubleshooting is the Tachometer. I am getting a signal from the coil at the tach, but i dont know if the ECU is getting that signal. That would explain after the ignition start sequence it doesnt see any RPM and doesnt tell the injectors to fire causing the engine to stop quickly every time. I am trying to find a pin that the ECU would recieve this information but cant find one.

I understand that, AI is a smorgasbord of articles massaged into one. He mentioned he was searching AI. The reason why I asked the question.

Yarb, the 1980 EFI book is the official Nissan electrical troubleshooting manual. It's basically the FSMs stripped down to the bare essentials and combined in to easy to use charts and instructions.

The most reliable source is the FSM that can be downloaded on this site

So what do you recommend? Keeping the 1.5 ohms pertronix and 1.5 ballast resistor i the circuit?

I'm reading through some stuff and looking at information the AI and it brough up the thermotime switch. it functions at start up for exactly the amount of time my engine stays working.

Besides cgsheen1's suggestion, tapping on the injector bodies will often break them free. In your case though it might take a while to get all six free. The engine will run on three cylinders. Sounds like you don't have any injectors working.

Are you saying that it still will not continue to run? That you have to do this trick over and over? That would make sense. Each "Start" squirts some fuel in to the intake manifold. The cold start system would be working corectly. Not a problem. Still sounds like your injectors are not opening. Pin 1.

1980 EFI Bible.pdf

@Toiletduck34 Where did you find this reference material?

sorry im refeering to the cold start valve. I thought i wasnt getting enough fuel after the initial start and checked the fuel pump and its sending fuel, the filter is staying full. there has to be something that stops sending a signal of some sort after the start procedure because I ran a test. Test: started the car and let it run for 8-9 seconds. the moment i hear it start to fail i click over the egnition for just a moment. the starter grinds for a milisecond... BUT the engine continues to run. I did this 4-5 times to let it run for ~1 minute and it idle perfectly. ****maybe im only getting gasoline from the cold start valve... when it stops im not getting anything from the 6 injectors.****

There is no cold start sensor. You're at a good point to read the Engine Fuel chapter.

Sean, you need to improve your reading and comprehension skills. My messages are clearly meant to help the guy find you. And my second message implies that it was his fault you didn't want to reply to him. Both messages are in your favor. Why DM a guy who doesn't respond to a customer's messages? And why try to help a guy run his own business? Not my responsibility. You're way off base and not making sense. Good luck with your business.

Shut the <blank> up

i added a new fuel filter a few days ago. I ran the old fuel out with the pump and added about 5 new gallons, ran that through until it cleared out. it should be good enough to keep it running. Im leaning towards now the cold start sensor and the thermal switches. still trying to understand all these system. these sensors are ~50 years old, im sure they arent working perfectly. I think im to the point i know the engine is good. i want to tear this entire engine bay apart, clean, replace and start from fresh.

The op had the wrong contact info and posted that. I apologized. Stfu? Okay I'll remember to do that in future post. Kindest regards Pip. Cliff

I've been stuck on this album for a couple of weeks now. I'll put on something else and after that finishes I'll say to myself... Let's give John Hiatt - Walk On another play.