Recent posts

#91

Modifications and Repairs / Intermittent `Bad´ Starting

Last post by Super fx - January 06, 2022, 10:21:40 PM

Hello,
Happy New Year to everyone,
I´m hoping someone can help me with some inside knowledge of vems.
I have a V3.3 (bought from Peep as a pnp as i really didn´t want to be going into the nittygritty diy of ecu´s at the mo) installed on a Porsche 944 turbo. It starts, idles and runs great on a good start BUT on about 50% of starts it is BAD and has a light misfire (like a vac leak or weak spark), almost dies on accel (like a carb accel pump not working) and has `hard´ backfires on rapid decels (like a bad vac leak).
Once started in this state it will not recover unless restarted (ecu reset ?) and is immediately obvious by the popping sounds at idle in the exhaust.
At idle (800rpm) The 02 is approx .05 higher than a good start (i presume unburnt fuel?) and very unstable as are the rpms & 02 with tps held at 4%.
Turn it off & on again and it will run perfect - 02 @ 99 or wherever it is set, no misfire, backfire etc.
I´ve tried all external troubleshooting i can find & think of, and am now wondering if its possible for Vems to initialise and latch in a state that can cause these issues until the power is cycled.
I was running WS with new leads, but have put the stock coil n cap/leads back in, tried 3 new ws coils, deactivated and plugged the IAC, 2 new sets of plugs (resistor & non), checked for vac leaks, swapped inj, ign Channels & pins, jiggled harness´s conned out connectors, checked tps sweep, disabled inj cha´s during idle but cant find anything wrong.
Trigger logs look good, timing strobe looks good steady n solid also.
Cylinder head recon & turbo were replaced at the same time as installing vems.
Next thing i´m going to try is reinstalling the Motronic ecu but i was hoping for some ideas before doing that.
I´m not sure how to add a logfile...
Any advice appreciated,
Thanks !

#92

Triggering / Re: Mini MPi sectrig problem

Last post by FullGasCZ - January 04, 2022, 07:42:51 AM

Hi, i have problem with sectric on Mini Mpi, it is stock VR sensor and ecu dont accept this signal. It should be that voltage on the peak is too low? Or shape of curve is incorrect? The sensor is in the groove in the lobe of camshaft.

Thank You for answer

maybe your ecu is configured with hall trigger hw for secondary trigger?

No, ecu is configured correct. Or can i verify it somehow?

photo: https://ibb.co/M7WDYy2

on your paper it writes sec trigger hall, and you are using VR sensor for that, so that's your answer..

Really? i see Sec trig VR, where is the problem?

#93

Triggering / Re: Mini MPi sectrig problem

Last post by Kamuto - December 30, 2021, 06:42:10 AM

Hi, i have problem with sectric on Mini Mpi, it is stock VR sensor and ecu dont accept this signal. It should be that voltage on the peak is too low? Or shape of curve is incorrect? The sensor is in the groove in the lobe of camshaft.

Thank You for answer

maybe your ecu is configured with hall trigger hw for secondary trigger?

No, ecu is configured correct. Or can i verify it somehow?

photo: https://ibb.co/M7WDYy2

on your paper it writes sec trigger hall, and you are using VR sensor for that, so that's your answer..

#94

Projects & Installs / Re: Volvo S40 B4194T

Last post by Andy P - December 22, 2021, 11:33:24 PM

Hey, only a few years delayed response but there have been a few S40's on these boards running VEMS (myself included, another user Tcode as well).

That was back in 2008 though!!

#95

Triggering / Re: Mini MPi sectrig problem

Last post by FullGasCZ - December 22, 2021, 07:34:49 PM

Hi, i have problem with sectric on Mini Mpi, it is stock VR sensor and ecu dont accept this signal. It should be that voltage on the peak is too low? Or shape of curve is incorrect? The sensor is in the groove in the lobe of camshaft.

Thank You for answer

maybe your ecu is configured with hall trigger hw for secondary trigger?

No, ecu is configured correct. Or can i verify it somehow?

photo: https://ibb.co/M7WDYy2

#96

Triggering / Re: Mini MPi sectrig problem

Last post by Kamuto - December 21, 2021, 11:05:15 PM

Hi, i have problem with sectric on Mini Mpi, it is stock VR sensor and ecu dont accept this signal. It should be that voltage on the peak is too low? Or shape of curve is incorrect? The sensor is in the groove in the lobe of camshaft.

Thank You for answer

maybe your ecu is configured with hall trigger hw for secondary trigger?

#97

Triggering / Re: Mini MPi sectrig problem

Last post by FullGasCZ - December 20, 2021, 10:01:41 PM

https://ibb.co/D5HQbjk

#98

Triggering / Mini MPi sectrig problem

Last post by FullGasCZ - December 20, 2021, 09:55:20 PM

Hi, i have problem with sectric on Mini Mpi, it is stock VR sensor and ecu dont accept this signal. It should be that voltage on the peak is too low? Or shape of curve is incorrect? The sensor is in the groove in the lobe of camshaft.

Thank You for answer

#99

Modifications and Repairs / Re: ETC Module

Last post by jrussell - October 27, 2021, 09:08:50 PM

This isn't hard.

Either the pwm pad as Peep pointed out, or a spare injector output as Valdas pointed out goes to SSC6 pin 1 (Bridge control). SSC6 pin 6 (GND) needs to be connected as well, naturally.

Forget about the PFET, those aren't for ETC. Do that later if you need.

People should be ordering the ECU with ETC so you can just plug it in. Or order the ECU with the ETC mounted inside.

#100

Solenoids / Re: Correct VR6 OBD2 Idle sett...

Last post by jrussell - October 27, 2021, 08:59:26 PM

Best thing at the current time is not try to use the idle on that throttle. It's the worst throttle design I've ever seen. Use a throttle stop to get it to have a good idle between high and low idle rpms, and use ignition idle advance to dial it in.

That said, I've been working this week on trying some ideas for hardware to control that throttle. All concept so far and hope to start trying some things on the bench by the end of the week.