Triggersettings, simpletrigger + camsync questions.

[Erikk]

Hi!

Im helping a friend to setup his Porsche 944 with a 4cyl inline 4 + turbo.
Firing order is 1-3-4-2.

VEMS v3.6 with 1.1.67 firmware.

Both triggersensors are Honeywell 1gt101, triggering on 2 spots on the crank and 1 on the Cam.

I´ve tried with these triggersettings, but dont know if its correct?






The sparks are not constant, it fires a few sparks to begin with, sometimes no spark at all.

Using IGBT´s to fire VAG-Coils with 1,1kohm pullup.

Maybe the sync-sensor is located too close after the cranktrigger.
If I get this correct, the sync-sensor resets the [h2] table, if so it should start firing the 3rd cylinder, since the sync sensor triggers just after cyl 1 has been triggered.

Is there any more information you need?

Sorry for my bad english, im in a little bit of a hurry right now.

Thanks in advance!

/Erik.

[rob@vems.co.uk]

Is the RPM constant?

I don't think that the IGBTs with a pull-up are the way to drive those coils - why not use the stepper motor outputs?

[Erikk]

Yes, RPM on cranking is about 200-220rpm, so its seems fine.

We are using a prebuild Vems-harness (v3harness), and two of the cables were already stifted to the IGBT´s, and i dont have the tool to remove them atm, so I just connected the other two to the IGBT´s also.

I think there are people who have controlled these coils with IGBT+Pullup?


Settings seems fine?

Best regards.

[rob@vems.co.uk]

if you're getting a clean RPM then the trigger settings look to be fine.
There is no special tool needed for pin extraction - there is a locking tab at the top of each connector, a precision screwdriver or point can be inserted to raise the tab up - and the pin connector will slide out easily.  This is better documented on page 14 of this: http://www.vems.co.uk/VEMSSchematics/1+2JZLoomGuide07May2008.pdf

[Erikk]

if you're getting a clean RPM then the trigger settings look to be fine.
There is no special tool needed for pin extraction - there is a locking tab at the top of each connector, a precision screwdriver or point can be inserted to raise the tab up - and the pin connector will slide out easily.  This is better documented on page 14 of this: http://www.vems.co.uk/VEMSSchematics/1+2JZLoomGuide07May2008.pdf

So the Reference tooth table doesnt reset at sync signal and should be:
3
2
1
0
?

We will try using the stepper output instead tonight.



Edit:
I´ve totaly missed to invert the ignition driver output, which is a must if I want it to drop ground as dwell instead of grounding the dwelltime.
As the ground shorts out the pullup resistor.

Am I right?

Edit nr2:

I called the owner and asked him to change to Inverted output, then the spark seems to come as it should!

Sometimes all you need is thinking things through

[lost]

Are you sure about angular widh of tooth? Mine is 6deg od 60-2 wheel.

And if you have active vag coils with 4 pins, you need to run them with stepper outputs on ec18 connector.

[Erikk]

Are you sure about angular widh of tooth? Mine is 6deg od 60-2 wheel.

And if you have active vag coils with 4 pins, you need to run them with stepper outputs on ec18 connector.

360/60 = 6
360/2 = 180

So I think it´s right?

I know Mattias has driven these(and other active coils) coils with IGBT and Pullup, so I´ll give it a try.

[peter_jensen]

if you're getting a clean RPM then the trigger settings look to be fine.
There is no special tool needed for pin extraction - there is a locking tab at the top of each connector, a precision screwdriver or point can be inserted to raise the tab up - and the pin connector will slide out easily.  This is better documented on page 14 of this: http://www.vems.co.uk/VEMSSchematics/1+2JZLoomGuide07May2008.pdf

This is the best documentation I ever seen “i wish we have one like that explain haw to set up Vems trigger ”

[Erikk]

After a chat with Emil the Porsche is now running fine!

Here´s the correct settings.

We are now using the Stepper outputs instead.

Stepper A = Cyl 1 .. B = Cyl 2 .. C = Cyl3 .. D = Cyl4

[lost]

are you using resistors in series, what coils do you use? 115R?

[Erikk]

They are just connected directly to the Stepper outputs.

Its not the 115R or L , but I think it´s the same pinout!

[MWfire]

it's recommended to have ref tab for faster start-up(cranking)
3
2
1
0