Author Topic: Unstable dwell  (Read 16547 times)

Offline JTY

  • Jr. Member
  • **
  • Posts: 17
  • BHP: 0
Unstable dwell
« on: June 24, 2010, 09:21:20 am »
Vems v3.6, firmware 1.1.74

Problem is unstable dwell time, in ignition output test mode dwell is jumping between 4ms - 90ms in random way (coils got little warm  ;D).
Same is while cranking, dwell is set to 4ms in setup.
Board was ordered with 6+2 IGBT's, but current setup uses TTL coils so 6x IGBT's where removed and IGBt's pins jumpered,
same way as 2 TTL outputs on the board. It worked fine for while, but then suddenly dwell started to jump.
Any ideas ?
Should the dwell be same in test mode and normal run mode ?
Ignition output has been tested with digital scope.
« Last Edit: June 24, 2010, 09:34:13 am by JTY »

Offline gunni

  • Hero Member
  • *****
  • Posts: 1492
  • BHP: 37
Re: Unstable dwell
« Reply #1 on: June 24, 2010, 10:17:24 am »
Post your ignition settings.

Offline JTY

  • Jr. Member
  • **
  • Posts: 17
  • BHP: 0
Re: Unstable dwell
« Reply #2 on: June 24, 2010, 10:54:42 am »

Offline JTY

  • Jr. Member
  • **
  • Posts: 17
  • BHP: 0
Re: Unstable dwell
« Reply #3 on: June 24, 2010, 01:05:02 pm »
I tried newer firmware 1.1.78 but no difference.
Could it be hardware problem ?
Where can i find schematics for v3.6 board ?


Offline mattias

  • Global Moderator
  • Hero Member
  • *****
  • Posts: 1075
  • BHP: 41
    • Sävar Turbo Site
Re: Unstable dwell
« Reply #4 on: June 24, 2010, 08:12:15 pm »
Your configuration file is so messed up I don't know where to start..  I recommend loading my config file to your ECU and drag'n'drop your file over only the dialogs that are specific to your setup. Those are primary trigger and ignition settings, and your ECU calibrations.

Offline JTY

  • Jr. Member
  • **
  • Posts: 17
  • BHP: 0
Re: Unstable dwell
« Reply #5 on: June 24, 2010, 10:44:15 pm »
Your configuration file is so messed up I don't know where to start..  I recommend loading my config file to your ECU and drag'n'drop your file over only the dialogs that are specific to your setup. Those are primary trigger and ignition settings, and your ECU calibrations.

Okay no it seems to be stable, i had some triggering problem with your config, even if i changed triggering fields smae as old config.
But when i change all triggering settings with BMW_M20 template i got it working, but if i enable cam sync triggering show again wrong RPM info.
If i disable cam sync from the menu it has no effect, only choosing BMW_M20 template helps.
Any ideas ?

Here's both configs:
http://oh1jty.toimii.net/auto/vems-supra-non-working.vemscfg
With cam-sync enabled
http://oh1jty.toimii.net/auto/vems-supra-working.vemscfg
Without cam-sync enabled

Offline JTY

  • Jr. Member
  • **
  • Posts: 17
  • BHP: 0
Re: Unstable dwell
« Reply #6 on: June 25, 2010, 07:46:44 am »
I flashed 1.1.70 firmware and now i can enable and disable cam sync without messing all triggerin settings.
But still have problems with cam sync, if i enable it i loose RPM info (it show 100RPM if triggering with 1000RPM).


It would be great if vems firmware development started to use two trees one for devel version and one for stable version firmwares (like linux 2.4.x stable, 2.5.x devel) or mark development version with alpha/beta/rc tags, now there is no way to know which firmware is "Okay" when you use vemstune firmware uploader tool. It's too easy to mess everything very bad woth current way.
Also it would be good to have some built-in sane configurations for different firmware versions in vemstune. It would help people who are new with vems to get things working faster, because the documentation is very bad and wiki is confusing and vemstune seems to be pretty unstable and creating messed configuration pretty easy.
I have been using many ECU tuning software and vemstune is not the worst, it has many features that are really nice and good to have, but it has many things that are so unlogical and odd that makes my head hurt.
It's nice to have custom gauge candy and all sorts of different display modes, but please make the software stable before all the candy. I would understand all of this if vems were still open source project or maybe that's the problem why it's so messed up ;D
Vemstune developers should checkout TunerStudio, that's one great piece of software.


Offline Jamo

  • Full Member
  • ***
  • Posts: 129
  • BHP: 6
Re: Unstable dwell
« Reply #7 on: June 25, 2010, 09:06:22 am »
I flashed 1.1.70 firmware and now i can enable and disable cam sync without messing all triggerin settings.
But still have problems with cam sync, if i enable it i loose RPM info (it show 100RPM if triggering with 1000RPM).


It would be great if vems firmware development started to use two trees one for devel version and one for stable version firmwares (like linux 2.4.x stable, 2.5.x devel) or mark development version with alpha/beta/rc tags, now there is no way to know which firmware is "Okay" when you use vemstune firmware uploader tool. It's too easy to mess everything very bad woth current way.
Also it would be good to have some built-in sane configurations for different firmware versions in vemstune. It would help people who are new with vems to get things working faster, because the documentation is very bad and wiki is confusing and vemstune seems to be pretty unstable and creating messed configuration pretty easy.
I have been using many ECU tuning software and vemstune is not the worst, it has many features that are really nice and good to have, but it has many things that are so unlogical and odd that makes my head hurt.
It's nice to have custom gauge candy and all sorts of different display modes, but please make the software stable before all the candy. I would understand all of this if vems were still open source project or maybe that's the problem why it's so messed up ;D
Vemstune developers should checkout TunerStudio, that's one great piece of software.




The default configs are there, in the defaultconfig directory  ???

Offline rob@vems.co.uk

  • Hero Member
  • *****
  • Posts: 3115
  • BHP: 49
    • VEMS Forum
Re: Unstable dwell
« Reply #8 on: June 25, 2010, 11:12:51 am »
Never known the stock 1JZ or 2JZ cam trigger to work with VEMS - Or any number of other ECUs for that matter.

Offline JTY

  • Jr. Member
  • **
  • Posts: 17
  • BHP: 0
Re: Unstable dwell
« Reply #9 on: June 25, 2010, 10:55:49 pm »
Never known the stock 1JZ or 2JZ cam trigger to work with VEMS - Or any number of other ECUs for that matter.

No we are not using stock cam trigger, 60-2 wheel on crank with HALL and 1 tooth on cam with HALL

Offline rob@vems.co.uk

  • Hero Member
  • *****
  • Posts: 3115
  • BHP: 49
    • VEMS Forum
Re: Unstable dwell
« Reply #10 on: June 26, 2010, 06:40:47 am »
Run wasted spark then

Offline JTY

  • Jr. Member
  • **
  • Posts: 17
  • BHP: 0
Re: Unstable dwell
« Reply #11 on: June 26, 2010, 09:28:20 am »
Run wasted spark then

Why can't we run full seq. ?
Car is allready wired with TTL COPS on each cylinder, everything in place.
I have tried to find projects that run vems with 6cyl inj. and ign. seq., but no luck.
Does this mean it's not working in current firmwares ?

btw. we got the car running yesterday wit 1.1.70 version without camsync.

Offline gunni

  • Hero Member
  • *****
  • Posts: 1492
  • BHP: 37
Re: Unstable dwell
« Reply #12 on: June 26, 2010, 12:00:38 pm »
You need a single tooth cam sync to make it work.

I´ve used camsync on a 60-2 + 1 on a BMW M50 and it works a treat.

Offline rob@vems.co.uk

  • Hero Member
  • *****
  • Posts: 3115
  • BHP: 49
    • VEMS Forum
Re: Unstable dwell
« Reply #13 on: June 26, 2010, 03:44:21 pm »
You can run seq injection and wasted spark on COPs.

Offline JTY

  • Jr. Member
  • **
  • Posts: 17
  • BHP: 0
Re: Unstable dwell
« Reply #14 on: June 26, 2010, 05:36:45 pm »
You need a single tooth cam sync to make it work.

I´ve used camsync on a 60-2 + 1 on a BMW M50 and it works a treat.

Yes that's same setup i have.
I got it working with camsync, engine runs pretty good with full seq inj+ign.

Picture of the setup (supra 6cyl + eaton + zex nitrous):