280zx L28et ignition setup and testing

[floppy]

There is another thread for no rpm on this car... Still trying to sort that out...

This is a 1983 turbo motor that was running MS1Extra from the stock distributor with an internal CAS(I think) and a VB921 running the single coil.

It has been upgraded to MSII and I am trying to figure out the best way to run the ignition. After "fixing the wiring" , mostly redoing the really bad grounds, there was no rpm signal. This prompted me to do more research into this motor.

What I found was that the preferred setup is the one that I had before... Rats!

Now I am trying to decide how to move forward for the best result. IMHO- EDIS is the right thing to do but too much work to finish this "I'll help you out project". I know what you are thinking Ken.

It looks like the way to go might be with DIY's trigger wheel in the dizzy and the BIP373 to trigger the coil. Any thoughts?

Is it necessary to replace the VB921 with the BIP373? Is there a way to test the VB921 circuit?

Also- I have tried testing the dizzy with no success. I took it out and applied power and ground to the Black and B/W leads and used the LED tester with the right polarity to check the signal from the signal wire(primary and secondary). Spun it by hand and with a cordless drill. Nothing... What is the right way to test it?

Now that I am married to this project I sure would appreciate your help. Mark

[Matt Cramer]

What tools do you have available to test the VB921? Some problems can show up on a Stim, others are hard to find without an oscilloscope.

[floppy]

I only have the stim, no O-scope...

[Matt Cramer]

First, as you're reporting no RPM on the car, do you get RPM on the Stim?

[floppy]

First, as you're reporting no RPM on the car, do you get RPM on the Stim?

Yes there is rpm with the stim.

[Matt Cramer]

Ok. Try slowly turning the distributor while checking the voltage at pin 24 with a volt meter. It should switch from 0 to 12 volts and back six times per distributor revolution. Let me know what you find.

[floppy]

There is no signal produced when the distributor is tested per your instructions.
EDIS went on last night but still not seeing a tach signal? it started momentarily so the EDISitself must be working, right.
Going to replace the tach wire tonight?
Does EDIS send the same type of signal for testing?
BTW- this controller sees rpm on my other car but shows no advance in TS? Reconnects to TS every 10 seconds or so;sometimes the middle LED stays on...
MSII-2.905 on both controllers.

Appreciate the help, this has been a tough project...

[Matt Cramer]

EDIS should put out a signal of its own, but may not be able to put out a signal at near zero RPM like an optical distributor.

[floppy]

Although not very definitive the edis does produce a voltage of about 3.5 before cranking and them drops off on the DMM.
There is tach signal now and it fires.
Thanks, mark

[floppy]

All is well now, except for some additional mysterious car wiring issues. And my buddy forgot to tell me the name of the car, "Christine". Thanks bro. Every time I hit a new weird issue with this car he says oh yeah, there was this thing going on... How about letting me know up front!!!

Turns out that there is some kind of issue with the ignition switch circuit that does not reliably power up when the key is turned on. The actual ignition switch is suspect as it lights right up if you cycle the key again. Much of the original ECU and external regulator are/were still attached so there could be something funky going on there. One oddity is that one of the two fusible links gets hot rather soon after starting but never goes to failure. And if unplugged while the car is running it starts to run poorly. Weird because if it is powering the associated circuit it should just die.

BTW- Don't forget to ground the EDIS coil pack to the engine if you mount them to the firewall... Just saying it might run better.

Thanks for helping out, Mark