1976 280Z Restoration Project

[Zed Head]

Sounds like it's running on 5 and the dead/bad cylinder has a stuck valve or something.  Or it's running on 5 and it's running lean, and the weak cylinder doesn't have enough to keep firing, just an occasional kickback.  What happens if you  increase injector open duration to make sure you have enough fuel?  These engines love their rich mixtures you know.

That video was about perfect.  It played, it was small (quick download) and it showed some stuff.

[wheee!]

Thanks Zed. I checked the injector harness with my brand new Noid light kit. They are all pulsing. I also checked the injectors previously. I am set up for 310cc volume on these too.
It sounds like 5 cylinders to me too.

[Zed Head]

If you're running 310 cc injectors then the open time for idle is very short.  You might have a sticky injector or just be on the edge of control.  So, making it richer might get you to where 5 run rich and one runs right.  But it might show you something.

I said increase injector open time but on your settings it might be something else.  Whatever setting adds fuel.  You could even just increase fuel pressure as a test.

p.s. the popping might be from enough fuel getting sucked over to the dead cylinder to make it pop.  You might just have a dead injector.  The noid light shows that injector got current but not that it actually opened.  With 310 cc, open time is going to be a tiny faction of a second at idle.

The more I ponder, the more it seems like a stuck injector.  Just a view.

p.s. 2 - are you sure that fuel pressure is maintained after it starts?  It really should have kept running, on 5.

Edited September 18, 2020 by Zed Head

[wheee!]

Fuel rail pressure is right on the money. I tested the newly rebuilt injectors and they all pulse properly with 9v applied.

I have a new tune to load when I get back to the car. The tuner changed a few settings. TDC might have changed when I moved reluctor pickups in the CAS. My timing light still shows 10 degrees BTDC at the current setting though...

[wheee!]

Got so much done today!!
... cleaning that is. Half the shop done!

[Patcon]

You are so close! You've really made good time...

[grannyknot]

It looks great, where are you with the tune, is it running nicely yet?

[wheee!]

I have a new CAS from OneSix on its way. We are testing a theory that the one I have may be a dud.

[wheee!]

Ever hear the story about the guy that wired his injectors and COPs for Haltech in 1-5-3-6-2-4 firing order instead 1-2-3-4-5-6 cylinder order?
Yeah, that’s me... I’m the idiot...

[Captain Obvious]

You're kidding... Wrong firing order? That was the issue?

[wheee!]

That is one of the issues... I have a few more tuning bugs and hopefully will have it running soon.

[wheee!]

Somehow I have an injector issue too.