78 280Z - no injector pulse

[kelley0352@att.net]

3 minutes ago, Zed Head said:

This does not really mean anything.  You touched the negative post of the coil?  Was the key on?  Did the test light flash?  Was the engine running when you did that?

The details will have the clues.  You're just not providing enough information.

The key was on & engine not running..........& yes I had juice there on the neg side of the coil. I also tested all the coils with an ohm meter & got 1.8 to 2.7 readings

Edited July 18, 2020 by kelley0352@att.net

[Zed Head]

5 minutes ago, Zed Head said:

Did the test light flash?  

The details will have the clues.  You're just not providing enough information.

Details...

[kelley0352@att.net]

4 minutes ago, Zed Head said:

Details...

it lighted up but did not pulsate or flash. 

Edited July 18, 2020 by kelley0352@att.net
grammer

[Zed Head]

Did you try to start it with the light still connected?  That will not work.  The light does not allow the circuit to break so you'll get no spark.  Disconnect the light and try to start it again.

[kelley0352@att.net]

7 minutes ago, Zed Head said:

Did you try to start it with the light still connected?  That will not work.  The light does not allow the circuit to break so you'll get no spark.  Disconnect the light and try to start it again.

This is my red Z & No I did Not try to start it with the light still connected. I just went back out to my white Z that had the original problem & I have 12v on one side of the injector plug & not on the other side. I jumped the ground to the #'s 14,15,30-33 and it clicked once & quit. I connected the noid to #6 cyl and got a single blink when grounded the first time I grounded it and nothing afterwards.

[Zed Head]

2 minutes ago, kelley0352@att.net said:

 I have 12v on one side of the injector plug & not on the other side.

Is this with all of the injectors plugged in or did you just disconnect one?  If you disconnect just one you'll see voltage on both side because it's a parallel circuit (thanks CO, from the past) and you're measuring voltage from the other injector circuits.  If they 're all disconnected and you only get one pin with power that's normal.

Have you tried starting it with fluid again?  That's one of those previous suggestions.

When you jump around from thing to thing it's very difficult to solve a problem.  You have to be methodical.  Go back and recheck things often to be sure that they still apply.  If it won't start now with starting fluid then you might have a new spark problem.  No use looking at injectors if you don't have spark.  Just because it started on fluid 5 years and 11 months weeks ago, doesn't mean it will now.

And, maybe most significant...just realized when this thread started.  August 2014.  If your fuel is almost 6 years old you should probably change it.

[Zed Head]

On 6/26/2020 at 9:20 AM, kelley0352@att.net said:

well I am still not understanding this problem with the failure of my injectors that have 12v juice & no pulsating Noid light. Everyone is talking about the #1 pin in the ecu. Well what & where is that & what is it suppose to do? Test it while it is hooked up to the plug is impossible! Makes no sense to me.

Actually, just realized that I have no idea who kelley0352 is or what, generally, the problem is.  Looks like he just glommed on to Virto's thread.  When he said "still" I assumed that he was the OP.  Maybe not.

Oh well, the chaos continues...

Try some starting fluid and see what happens.

Edited July 18, 2020 by Zed Head

[kelley0352@att.net]

5 minutes ago, Zed Head said:

Is this with all of the injectors plugged in or did you just disconnect one?  If you disconnect just one you'll see voltage on both side because it's a parallel circuit (thanks CO, from the past) and you're measuring voltage from the other injector circuits.  If they 're all disconnected and you only get one pin with power that's normal.

Have you tried starting it with fluid again?  That's one of those previous suggestions.

When you jump around from thing to thing it's very difficult to solve a problem.  You have to be methodical.  Go back and recheck things often to be sure that they still apply.  If it won't start now with starting fluid then you might have a new spark problem.  No use looking at injectors if you don't have spark.  Just because it started on fluid 5 years and 11 months weeks ago, doesn't mean it will now.

And, maybe most significant...just realized when this thread started.  August 2014.  If your fuel is almost 6 years old you should probably change it.

This thread did not start aug 2014. It started June 2020.  & I have pumped some into a can & looked at it. Both fuel filters are new.The fuel is good.

The parallel circuits makes sense, I hadn't thought of that

Edited July 18, 2020 by kelley0352@att.net

[Zed Head]

On 8/27/2014 at 11:25 AM, Virto said:

I'm starting this thread as a bit of a placeholder, moving this issue out of my old exhaust manifold/status thread since it's likely I'll need help.

The background is listed in the exhaust thread, so I'll keep it focused on the EFI here. Bottom line, car hasn't run in a year, head was pulled and tanked, and the car is back together now. The car will crank easily but not fire. Injectors show 12V but no pulse via NOID light.

Zed Head has helped give me some places to start - I'll likely only have access to the car over the weekend, so I can't just run out and mess around, as much as I'd like to.

I'll add to this thread as time goes on with status and results. If anyone else has any questions or direction (/wave FastWoman, ) I welcome your input.

This is the "start" of the thread.  Virto even uses the word start.

[kelley0352@att.net]

Virto's thread, not mine, I just found this site & just joined it to figure out this problem. I have been wrenching since I was 10

I am starting to think that the ECU is intermittently bad, (goes in & out of operation)

Edited July 18, 2020 by kelley0352@att.net

[Zed Head]

4 minutes ago, kelley0352@att.net said:

Virto's thread, not mine, I just found this site & just joined it to figure out this problem. I have been wrenching since I was 10

I am starting to think that the ECU is intermittently bad, (goes in & out of operation)

I don't think that you understand what "thread" means.  You jumped in on Virto's thread.  You don't have a thread.

The ECU's do go bad.  But you said that the one you tried worked fine in your other car.

"I pulled the ECU out of a running 1978 Datsun 280 Z and put the other one back into another running 280Z and it is working just fine in that car."

[kelley0352@att.net]

19 minutes ago, Zed Head said:

I don't think that you understand what "thread" means.  You jumped in on Virto's thread.  You don't have a thread.

The ECU's do go bad.  But you said that the one you tried worked fine in your other car.

"I pulled the ECU out of a running 1978 Datsun 280 Z and put the other one back into another running 280Z and it is working just fine in that car."

Yes I did do that with the ECU & you are correct, I don't know what Thread means, although I have asked & gotten no reply.