zxtrbo

We have progress!
I got a noid light and verified no spark, then checked injector wires from ecu and they passed. I then decided th go back throught the CAS, thinking no signal to the ECU no spark. I took CAS reinstalled it and Bang! She started. It currently wont idle and backfires through the the exaust, but i have been installing an intercooler and still need to double check piping is sealed properly.

zxtrbo

More progress! I took out the distributor checked wiring and put it back in and it started, but still runs really rough(barely at all). I have went back through all the usual culprits and everything seems to check out. Chts,vacuum,etc. I need to get a fuel pressure guage but in the meantime, i cleared the codes on the ECU to see if that could help me chase down problem. The computer gave me a bunch of codes.

Question what codes stay on after this swap. I got code #21, 23, 24, 31, 41, and 14. It seems to me the ones i need to focus on are 21 and 23?

zxtrbo

Also the test in the z31 fsm starts by checking wire 5 and 3 to a ground but have no wire 3.

zxtrbo

Tested fuel pressure 27# with vacuum connected and 27# with no vacuum.
FPR or fuel pump?

NismoPick

You don't need a wire at ecu pin 3. 27psi fuel pressure is a bit low, but won't cause this issue.

#1: If it barely runs, it's most likely either flooding out, or the timing is way off. Did you remove the oil pump and shaft at some point? If that was removed and reinstalled one tooth off, then it will do exactly this.

#2: Pull and read your spark plug tips. Are they wet with fuel, or dry? Color?

#3: Check all efi harness grounds. Verify that ecu pins 28 & 36 have continuity to ground.

#4: Verify that you have correctly connected the MAF plug to the 280ZXT harness:
A: ECU pin 30
B: ECU pin 31
C: Ground
D: ECU pin 26
E: Switched power (Black white stripe)
F: ECU pin 33

#5: Disconnect MAF plug, and start engine to see if that makes a difference.

#6: You said you checked the CHTS... how did you check it? OHM test from ecu plug?


For distributor rotor check, see also: https://www.zdriver.com/forums/280zx...-timing-40948/

zxtrbo

GOT IT!
It wa the distributor rotor. I had not installed the little washer that alligns the rotor. Once again I would like to than you for not giving up. It was the information you provided that allowed me to figure this out.

NismoPick

So it's up and driving?

zxtrbo

Still have to put things back together, need a hose clamp for the radiator hose clamp. Live in las vegas and only have about 30 min a day thats not 115 degrees. Ill get back to you after the test drive. Next up! Electronic boost controler.

NismoPick

Nice! Which boost controller you going with? I used an HKS EVC IV for about 10 years and loved it. I thought it died so I upgraded to a Greddy Profec OLED.

And if you are on Facebook, make sure to join the group "280ZX Drivers".

zxtrbo

Turbo smart e boost, neighbor works a honda tuning shop got it cheap.

zxtrbo

Not sure if i should start a new thread, car ran great for a day then died at a stoplight. Actually while slowing down, not sure if it makes a difference.

Things checked so far,
There is no spark verified through inline spark checker and pulling dist wire. There is actually 1 spark while letting key off

Checked wire 5 and 8 for signal which i believe i have. I set multimeter to 20dcv grounded wires while cranking and appear to be getting signal. I also dont seem to have injector pulse used noid light and got no flashing. I did check injector wires from ecu and apear to have pulse.
Will the injectors fire with no spark? I would be leaning towards ignitor, but injectors dont seem to be firing either.
Also ignitor is grounded.

zxtrbo

I have continued to try to figure this out. I checked all ecu grounds. Got a hei ignitor still no spark it did start for about 10 seconds idled smooth then died. The only spark i get is after cranking at the same time the fpr shuts off it puts out 1 tiny spark. Im thinking ecu?? But dont want to just throw parts at it

NismoPick

I'd start with checking the CAS again... make sure the distributor and CAS inside are secure, and that the pigtail is completely plugged in at the distributor and round harness plug. Also wiggle that pigtail... I've had that be bad too.

zxtrbo

Copy ill check it again

NismoPick

I converted a stock turbo CAS plug to a VG33E CAS plug. Same white plug for the distributor, newer harness side:

zxtrbo

Ive checked the plug for ground and 12v power i have both, im going to look for a newer plug and rewire it. Im sure im missing something. It ran great for 1 day.

zxtrbo

Found a cas wire test on xenons. My cas harness passed. I will look to updatevin the future also took apart distributor. Every was in order. Im out of ideas.

NismoPick

If pin 5 is getting ground signal, then there's something wrong with the ignitor or wiring to coil. Verify that the black white stripe to coil is getting 12v. If so, the ignitor may be toast. Since the stock ignitor is fairly rare these days, you can use the VG30 / VG33 / KA24 PRW-2 ignitor with a few quick wiring changes. I actually only have that How-To on Facebook... guess I need to post it here on the forum too. lol.

zxtrbo

I put a hei ignitor in and no change. I have ground to it and power to the coil. I have read all over different posts that wire 5 should have gated signal, thats what causes spark? However im am unsure on proper test for that. Put multimeter on 20 dcv and while cranking i can see numbers, but not sure that is the signal im looking for. I read its 5v pulses but dont know how to measure. Same signal comes from CAS. Correct??

zxtrbo

I redid some wiring to ensure it was secure also added a groung to the ECU just in case. I then retested the cas wire at the ecu and got 5v signal that dropped up (meter is not fast enough) while cranking. This seems to be correct according to my searching.
I then checked the the yellow wire at the ignitor and got between 11 and 12v while cranking. My searching tells me it should be the same type signal as the CAS 5v and gating.
Can we verify this is correct

zxtrbo

Found new CAS in junkyard, Im up an running