[Kalns]

would it be woth the trouble to swap out vr sensor ? I have spare opel (c20ne or XE) by the looks its thesame, just dont know if the pinout is thesame...
ps any idea where in europe I could source max9926 vr-conditioner board ?

[PSIG]

The issue is more likely to be caused by the DSC. No idea why it doesn't work well in these engines with these boards. max9926 vr-conditioner works.

would it be woth the trouble to swap out vr sensor ?

Unfortunately, no one signal conditioner works for everything, and we don't have enough info to know why it will or won't, so we can't tweak it to work well. If you have tested to determine that's the issue, then certainly change it, as the (hopefully) easier solution.

[Kalns]

I would love to contribute to this, is there anything that I could try to do to filter this signal any futher ? maybe some additional capacitor is needed on input to smothen the signal at higher revs ?
I can upload a logfile if that helps some one or do some more mods to the speeduino.
As I wrote, I did a 10kohm potentiometer mod on vr+/- pins, it softened the error if I can say so, but did not remove it compleatly..

[NickZ]

ive build dozens of these and all run perfect, I only use the MAX9926 conditioners.

[Kalns]

Just noticed one think while searching for this answer to this bug.
1) My triggers are set to RISING
2) in diy-efi.co.uk reread description, and this is what I noticed

Code: Select all

This conditioner is non-inverting, set your trigger to falling edge.

When I set to Falling edge, I cannot even start the car, so maybe this is why there are issues with this conditioneer ?
Could this be that the engine is off by 1 revulution because of this ?

[PSIG]

Switching from Rising to Falling (with any conditioner) will move the signal to the other side of the tooth. Trigger Angle will require resetting. But (and there is always a "but"), if your VR sensor wires are backwards (reversed polarity) it will run with the wrong setting, but not with the right one.

I won't get into the pros and cons of running reversed polarity, but either test for sensor polarity (easy) or just try switching the sensor wires. It should run best with proper polarity and correct edge setting for the type of VR conditioner. This is a very common reason for issues, has users claiming "this conditioner won't work!", when it's not set-up right. Do as you like, but get it all set correctly to run which ever way you're doing it.

[Kalns]

Well now it runs, but has missfires 5k rpm + and i cannot get evenly to redline, free reving is not an issue, thesame goes for first and second gear, but in third forth and fifth gears is very noticable.

If I swap the crank / cam sensor pins +/- to -/+ and set from RISING to FALLING edge, could this solve the issue ?

[PSIG]

free reving is not an issue

That's usually a symptom of un-tuned fuel or incorrect dwell. But . . .

If I swap the crank / cam sensor pins +/- to -/+ and set from RISING to FALLING edge, could this solve the issue ?

It could. I would just try it.

[Kalns]

I changed dwell time from 3ms to 1.7ms and it was bether, less missfires in higher revs.
I am using stock ms42 coil pack 4 in 1

I`ll give it a try to swap pins and report back

[Kalns]

I changed dwell time from 3ms to 1.7ms and it was bether, less missfires in higher revs.
I am using stock ms42 coil pack 4 in 1

I`ll give it a try to swap pins and report back

So I did swap cam and crank pins around, filtering set to NONE
Trigger set to FALLING
Was able to start the car, but random sync loses all over the place at idle, tachometer jumps from times to times around, in TS i saw a spike from idle to 9k rpm
Trigger set to RISING
a bit bether but sync loses still noted

At the end I reverted pins backto OEM placement and installed 4,7k ohm resistor over crank pins
sync loses are a lot less than before but still sometimes at higher rpm happen, atleast now I can start to combat boost control.

BTW about boost control, Is this normal ?
boot cut set to 170kpa, in logfiles I have noted that acctual engine protection enables around 175-178kpa and nothing happens, boost still climbs to 210kpa. Is there an hardcoded margin over limit?

EDIT:
Today I swaped m42 vr sensor for another, from old opel calibra 2.0 8v engine, basic physical dimensions are thesame and everything fits nice.
at the first moment it seemed to solve the issue, how ever, after some few puls it started to behave thesame..
I have not moded my MEGA for reset control, but have bridged pins for reset control on the ecu board.
Sometimes my laptop disconects when this missfires ocure, could this maybe also connected some how ?

At the moment I am trying to source spare parts for max9926 board or assembled version..