I already have a VEMS V3.8 ECU with auditrigger/camhall inverter (suitable for VR/VR and VR/auditrigger)

Installing Audi 4.2 Liter V8 ABH code engine.

Ignition: MembersPage/Norbitron/AudiV/IgnitionTransformers

The engine has Auditrigger (every 2nd sectrig VR pulse masked by cam-HALL) like Audi AAN.

c272: 272 teeth on full engine cycle, so 34 tooth between events:

Can this trigger setting work?

Will check your annotated vemslog.

Triggerlog hint:

Please publish triggerlog (obviously that is the way to proceed during trigger setup (even when it goes smooth without issue).

When capturing triggerlog, if configured for auditrigger, some pulses might be hided.


Old HV wire rubber insulation failed => Trigger error

The engine started up with VEMS, and worked fine for 2 weeks.

2017-06-03 (without doing anything special) I was driving on highway at 3200 RPM when I feel some missfire, the engine was shaking. Connected my laptop (VemsTune) I saw trigger error

(which might be the cause, or RESULT of ignition problem: confirmed, fixed after swapping the faulty HV wire).

Please verify config (with the one saved when all was good)

On lower RPMs there wasn't missfire/trigger error. Outside temp about +30deg. When i came back home at night (+12-15deg)the missfires came at about 2500rpm. And now comes randomly RPMs (even idle ?).

My measurements:

  • EC36/27 voltage with connected ecu/ign on=0.2V , At idle=0.34V, resistance between EC36/27 and EC36/26 = 1160ohm when ECU connected, disconnected ECU connector=1212 Ohm, Sensor resistance= 1210 Ohm
  • good, normal values, but still, connect a 27k..47k pullup resistor between EC36/27 and +5V (this results in "stronger pullup", resulting in 0.3 .. 0.4V DC bias, and more noise tolerance, although still might not tolerate ignition related pulses)
  • EC18/12 voltage with connected ecu/ign on=0.0V , at idle=0.22V, resistance between EC18/12.EC36/26 = 548ohm when ECU connected,disconnected ECU connector=1216, Sensor resistance =1215Ohm
  • EC36/13 voltage = 4.1V, on idle = 3.8-4.0V

Scope measurements:

cranking1-2-3.png - 3 trigger

cranking1-2-3L.png 3 trigger lower resulotion

idl1-2-3.png 3trigger on idle

idle1-2.png Primary and secondary trigger on idle

idle2-3.png Secondary and HALL trigger on idle.

Triggerlog with undivided settings:

Triggerlog when trigger error visible. I don't know what is the actually rpm:

I sent an url with vemslog.

Here is a slow acceleration in 4th speed then enginebraking. You can see the trigger error when i accelerate and also with engine brake when fuel is off.

The VE and IGN tables aren't 100% yet.