Inthenameofweez

I got a new ignition relay in there and no change. Brand new battery as well. Gauge lights work, engine cranks, and spark is there. I'm going to replace plugs and check compression just as a maintenance item. Noid light still not lighting on the individual injectors. Bu the cold start injector lights like a GD Christmas tree. And I know it's spraying fuel because I'll get a random fire from that fuel working its way into the cylinders... Help? I wanna drive this damn thing!

So, I found a common link between all of my issues. The ignition relay. Sure enough: So i tried to repair the ground with some solder of my own: I got the dash lights working. Brake indicator and tach are now working. Still no fuel indicator though. And no fuel injector pulse. I heard some shorting, and unfortunately I let the internal positive cables of the relay touch the negative body of the relay. And it burned the relay up. So I'm hoping that a new relay will solve all of these issue. Not sure what else could be causing no injector pulse. I just hope I don't have the same issues as this guy: http://forums.hybridz.org/index.php/topic/72897-280z-ignition-relay/ Until next year!!! That's all the wrote.

Here are some pictures of what I'm working with. There are 3 good fusible links. I have cleaned and verified that full continuity exists. The 4th one has been ghetto rigged because it obviously burned itself to death and melted the plastic case and wiring itself. I have questions about a few different issues.... Right now I have no dash lights, and no "BRAKE" or Battery light indicators. Before I started repairing things (main relay and fuel pump) I had blue/green dash lights and the previously mentioned indicators would light. Also, where does the lead from Pin 1 of the ECU connect to the ignition coil? I have verified that the fusible link controlling this wire is good, but I have not verified that the connection is good. I will include some pictures. Please give me a hint. Furthermore, there is a small blue capacitor looking unit next to the coil that had a wire disconnected from it. I have since soldered it back into place, but it changed nothing. What does this little cylinder do? And is it a replaceable part? Again, I'm really starting to suspect an issue with the ignition switch because I have no dash lights, the indicators no longer illuminate. Also, while testing at Pin 10 at the ECU, I only have 12V while in "ACC". I used a node light tonight and found voltage being sent to the cold start valve NO PROBLEM. However, there is no injector power. Zed Head, you mentioned a tachometer issue could cause no injector power. I am going to start reading the Body Electrical section, but in the mean time, could you expand on this issue? I'm am leaving the car for Christmas break (heading home) so I will not be able to work on it for a week. As I'm sure all of you will have family events during this next week, so I do not to hear a response for a while. However, even if you've got just a few thoughts, please share them. You can also see that the green fusible link seen in newer year Zs is not present on this car. This was manufactured in 2/77. Thank you again Datsun junkies and have a good holiday break from school and work.

I've got a node light. Gonna go play with it tonight. You're absolutely right. I pulled the cold start valve and it just cranks. I've also got a new battery. I'll be back online in a bit...

Omg. Everything makes sense now. I understand what you mean with the coil/cold start valve. So while I'm reading... what is your opinion as to why the injectors won't open? Bad/no signal from the coil? Edit: No. That can't be it. I've got 12V at pin 1...

I don't understand any of what you are saying. I'm not hunting an issue with the fire. I'm hunting an issue with the fuel. Ignition modules and lead wires make no sense as to why I can get it to run with starting fluid. And again, I have no green wires in my engine bay. I guess I needs to take a few shots of what I'm working with. http://www.youtube.com/watch?v=upVSDkadigg

Update: I can get a large amount of "sputter" while cranking. I am NO LONGER using starting fluid. There is some sort of a backfire in the intake manifold that is shooting a blue colored smoke out of the AFM. Not sure if I've got bad gas causing something or not. I'm going to get a 5 gallon gas can full of fresh 91 Octane and hope that I can clean out the junk in there. There are a few connectors inside of the engine bay that are creeping me out... I'll update in a few with more pictures and video of the "attempted" start.

Is what I'm holding referred to the Ignition Lead Wire? I have the FSM for my 77, but I don't see this green fusible link that is supposed to be clipped to the side of my relay cover. I will go check again. So if my tachometer is dead for some reason, I won't have injector pulse? As far as I can tell, while cranking, I have no tach reading...

Anybody have some ideas on what would cause the fuel pump to run normally and no fuel injector pulse? I am looking at the wiring schematic in the Bible and I see a few possibilities. I'm about to run out and start checking with a volt meter to see where my gap in power is, but what is more likely? Furthermore, where the heck is this damn fusible link? Is this in the engine bay? All engine bay links are OK and I still have no power to injectors. And this dumb ignition lead wire under the dash? WTF does it do? Haha.

No. A component issue more likely. Try playing with the flapper in the AFM.

Just because the relay clicks, does not mean that all circuits are operating properly. On page 137 of this manual: http://www.xenons30.com/files/FSM/77_datsun_280z.zip you will find the proper procedure for testing the power relay for correct continuity. You will need an Ohmmeter...

Yeah, I've checked pictures all over the internet, and my lines/rails are all hooked up right. I was listening with a screwdriver last night and heard no clicks. I'm wondering if the clicks are too quiet to be heard over the starter motor. Hoping to get plugs and node lights today. Any place that I can verify the proper order and placement of the spark plug wires other than the FSM?

Alright, so I've got a new fuel pump into the vehicle. Power relay is good. Sends fuel to the fuel rail like it's supposed to. It still won't start. It turns over like normal. It gets fuel. But either the fuel rail is clogged or the injectors are not opening. It is also possible that my plugs are simply so old and worn that all 6 have stopped firing. Or maybe the wires are mixed up. However, very unlikely, I will be replacing plugs and ensuring proper order of wires. In the mean time, I need to get some node lights to see why my injectors aren't opening...

We are having the exact same issues. I replaced my power relay (which I'm 150% sure is you issue) and I'm doing good. Still not running, but my pump runs in START like it's supposed to. The ACC instead of ON is a condition I also found. I'm pretty sure it's normal. Given that we're both having the same issue. The power relay is hidden right above the hood release. There are two large connectors plugged into it. Looks like this: http://www.atlanticz.ca/zclub/techtips/explodedviews/280z/77fsm/efi%20relay.gif

My parts car has a bad pump also. This one is shorted internally. (Sparks when touching each terminal). So I think I'm chasing more than one issue. I have a burned and replaced fusible link, a bad relay, and a weird response while turning the key to "ACC" and "ON". I'm wondering if any of those specialty Z shops in California have entire EFI harnesses laying around. I hope it doesn't come to that.... At least I have a parts car. Are the harnesses from 75 and (early) 77 the same? So given that I have the 12V signal going to the fuel pump while the key is "START", what can I confirm is good in this circuit? Simply the ignition switch, wiring, and relay? I may still have a bad ECU or one of the other inputs, correct? I don't even know if my dropping resistors or fuel injectors are okay. Ugh. I kinda just want to strip it all down and start rebuilding slowly after cleaning and verifying proper operation of each part/wire/component. .