Please plugoff USB serial connector

[wersch]

Non resistor spark plugs is for lawn mowers and methanol cars with dummy ignition  ;)

[fphil]

Still on the subject, has someone ever observed one second time jump in their log records?

[fphil]

You were right, definitely one needs sparlplugs with 50k resistance.

I first did not believe it since there was already 50k on the ignition cable (Beru connector).
I thought that the noisy speed given by Vems through the PS2 input was not related to the USB messages and comes from a noisy GRD. I improved the GRD, made a stronger pullup on the signal, the speed comes a little better.

Then , I thought to improved the grounding of the RS232 cable, nothing ... I scoped the coils for resistive versus a no resistive plug. nothing relevant.

Then I changed the plugs... The only way to protect the Vems circuit from any electrostatic transient voltage seems to be damping the transients at the origin.

Even if it could be obvious, I believe the recommendation for resistive plugs should better be put in the documentation (if not already there ;-))

btw. Another one should be to feed the IAC from an inj output. Then idle is fast tune. If fed from ign output, one (me) spares a lot of time and may need to work out as well the VE/Ign map at the idle point.

[NOTORIOUS VR]

@Notorious VR. Have you experienced wheelspeed from PS2? Do you know about this USB plugoff message?
I know that resistor sparkplug are ok, but I  do not know why non resistor sparkplugs still exist :)

Sorry only have experience w/ wheelspeed as configured by HU (on EC18)

[gunni]

You were right, definitely one needs sparlplugs with 50k resistance.

I first did not believe it since there was already 50k on the ignition cable (Beru connector).
I thought that the noisy speed given by Vems through the PS2 input was not related to the USB messages and comes from a noisy GRD. I improved the GRD, made a stronger pullup on the signal, the speed comes a little better.

Then , I thought to improved the grounding of the RS232 cable, nothing ... I scoped the coils for resistive versus a no resistive plug. nothing relevant.

Then I changed the plugs... The only way to protect the Vems circuit from any electrostatic transient voltage seems to be damping the transients at the origin.

Even if it could be obvious, I believe the recommendation for resistive plugs should better be put in the documentation (if not already there ;-))

btw. Another one should be to feed the IAC from an inj output. Then idle is fast tune. If fed from ign output, one (me) spares a lot of time and may need to work out as well the VE/Ign map at the idle point.

50K Ohm spark plugs?
Normally they are 5K and it makes a gigantic difference, I have had to do alot of work related to that and the return feedback is tons less with a 5k plug vs 0k plug

[fphil]

Glups, yes 5 kOhm for the NGKBPR8ES, you are right. Same that the Denso IW24 which were mounted before on the engine ( I have not seen Denso saying their plugs are resistive)
I hardly saw any difference with a standard scope. Did you use antenas  for measurements?
I understand now why the ignition  gates are sometimes deported far away from the ECU.

About the wheel speed circuit vs ps2 cable. Stupidly I wired mine that I  attached on the board after taking the cable off. When finished I realized that everything is already there  on the board just needing one solders some plugs ! ::)

[gunni]

for the feedback you need to measure voltage and current.