SR20det trigger errors while cranking

[JoeyJ]

Hello

I bought a Nissan S14 and a previous owner have installed Vems v3, I have no documentation or schematic and the car runs but needs some tuning, it has been through a couple of different owners since the install I think.

The problem is that sometimes when cranking I get trigger errors and the car wont start, but then sometimes it fires right up.
Either it starts immediately or it doesn't start at all no matter how long you crank it.

I have checked all grounds and wires but cant find anything obvious.
And when it starts it runs great without any trigger errors, the problem is only during cranking, so it seems like the wiring is in order..
Both primary and secondary triggers run in the same shielded cable, is it better to do 2 separate cables?

It uses the 24-1-1 CAS wheel configured as a 12-1 crank trigger
The secondary trigger is disabled but I don't know why since its wired.

Firmware 1.2.31

Here are config and a trigger log, first try it fired up the engine but the next try it doesn't start and shows trigger errors.
https://drive.google.com/drive/folders/0BwCHYOoFkUEuWjV2aWRJQm9wbFU?usp=sharing

Is it possible to get some information from the logs to see what the problem is? Bad power supply? Noise?

Enabling RPM filter, cam based trigger did not make any difference

[JoeyJ]

I have now tried with new wiring to the trigger with the same result, tried different grounds and 12v

This is how it looks when it wont start


Here it starts without any trigger errors


Any ideas?

Other than the trigger errors I can´t notice any difference from when it starts and when it doesn´t, it´s like 50/50 if it starts or not

[kurt06]

Interesting pattern. Hope someone knowledgeable would chime in.

[Kamuto]

I have now tried with new wiring to the trigger with the same result, tried different grounds and 12v

This is how it looks when it wont start


Here it starts without any trigger errors


Any ideas?

Other than the trigger errors I can´t notice any difference from when it starts and when it doesn´t, it´s like 50/50 if it starts or not

read about nissan trigger first :) then make log

[GintsK]

It looks 12-1 trigger. Not Nissan.
Most probaly You have 12-1 missing tooth wheel installed on crank and VEMS waits for camsync signal from modified optical sensor on cam.