N/A 4AGE 16V in AE86 - help needed, trying to "VEMS it"

[uzelac]

Found blown fuse, hope that's all. Took the loom of the car to add all needed stuff and tidy it up a bit.

While it is out i want to install MAP sensor for barometric corrections. ECU usually sits on the inside firewall. Should i put it in the case, somewhere near or in engine bay. I presume first option is best, just need to confirm it.
Plan to pull wires for Warning light, Shift light, one from 259ch0 just in case... stuff like that. Hope not to burn anything, and that engine will run when i return all that

[uzelac]

Revised wiring, much better positioning in engine bay. Wired diodes and some extra features, but still haven't try to use them.
Was extra careful, think i did all the cutting, soldering ... OK.
Still, had some suspicious behavior.

- Everything started OK, PC found and connected to VEMS, engine started OK.
- Few minutes in warmup engine just died.
- From that moment, touch pad on PC is showing awkward behavior, jerky motion and random clicking. Completely unusable. Keyboard working OK, VEMS and other applications starting/running/closing perfectly. Shutdown PC.
- Started engine without a problem, it worked for few more minutes and shutdown regularly.
- Confused, gone home.

PC works great now, no problems, seems like something from USB Serial adapter/VEMS or VEMSTune is messing up notebook while connected
Did anyone had similar problems? Some hint, what could a be problem ?

It can be relevant to say that i had some problems with USB-Serial adapter currently at use. It has some FTDI chip and in past it had issues with random disconnecting, for example while cranking or while testing coils-on-plugs.
Haven't got those issues while using other cable with Prolific PL2303 chip but that cable doesn't work with few netbooks i have so i prefer FTDI.
Prolific (that cable is made/sold by Conrad Eletronics, yellow one) works only with classic notebooks.
I came to conclusion that those netbooks have lower powered USB ports and they work only with FTDI cable, could be, not sure.
Prolific on the other hand when works, shows no issues, works without a problem, but need full notebook to work.

I suppose i could try with Prolific cable, maybe there won't be any problems, but now I'm not sure if my loom is OK.
Did anyone had problems with touchpad ?!?! Could that "messing up of PC" be related to some other problem, with loom/VEMS?

It would be great if FTDI is the problem, and everything works great next time with Prolific. But, I'm just not sure, should i even try. What's even more confusing is that VEMS and engine works great. Also, all sensors seem to work OK.

Could use some help, again :/.
Thanks.

p.s. really appreciate even if someone even read post this long

[GintsK]

Does engine dies only with PC connected?
I note engine cut for particle of second when VT start-ups/connects  to units with 1.1.97. Never saw this before! I have FTDI too. VT from September IIRC.

[uzelac]

Engine worked OK after PC disconnected, worked for a few minutes until i turned everything off.
Didn't want to connect PC after.

Will take VEMS and loom for a check tonight, want to go through all the grounds, maybe even replace them.

p.s. notebook works fine today

[uzelac]

I note engine cut for particle of second when VT start-ups/connects  to units with 1.1.97. Never saw this before! I have FTDI too. VT from September IIRC.

BTW I have same issue, not every start, and I use 1.1.96.

[GintsK]

Do you run notebook on batteries? Or?
External supply devices sometimes may create ground loops. It leads current flow through USB adapter. And this potentially can create problems like you have.

As I tune different cars quite often I decided to buy optoisolated USB->serial adapter per Rob suggestion. Otherwise time to time my adapters fries. Two times I had even MAX232 chip failure inside VEMS.

Gints

[uzelac]

Always batteries, all work done outside, no garage unfortunately.
What scares me, I had no such problems till yesterday, and then it happens the day I've done some "loom optimizations". Hmm..
Better safe than sorry, will check grounds tonight, maybe even redone them.

[stroft]

Does engine dies only with PC connected?
I note engine cut for particle of second when VT start-ups/connects  to units with 1.1.97. Never saw this before! I have FTDI too. VT from September IIRC.

I have same situation, 1.1.96 and 1.1.92 ECU's. Let's say i drive the car on the highway and VEMS is connecting, the engine sputters for millisecond and thats it. Except for that, i have no issues. I think it's normal ...

[GintsK]

Does engine dies only with PC connected?
I note engine cut for particle of second when VT start-ups/connects  to units with 1.1.97. Never saw this before! I have FTDI too. VT from September IIRC.

I have same situation, 1.1.96 and 1.1.92 ECU's. Let's say i drive the car on the highway and VEMS is connecting, the engine sputters for millisecond and thats it. Except for that, i have no issues. I think it's normal ...

It was not so before! For me it appers at time when VT counts pages.

[uzelac]

On hold until i solve these issues:

http://www.vemssupport.com/forum/index.php/topic,1844.0.html

[uzelac]

It looks like i solved the problem, if there was some at all. Rewired everything and it works like a charm.
Even at temperature below zero engine fired without a glitch. Very happy!

Back to connecting tachometer output, will try both options, "2+1 diodes" and "tacho booster" with dismantled relay and let you know which works.

[uzelac]

Temperatures droped heavily in past few weeks, and now daily is around zero, from -5 to +5.
Engine worked like a charm while outside temperature was 20-40 degrees C, but pressure and temperature are way different in winter.
I don't have MAP sensor and I'm not sure about MAT/TPS IGN and VE corrections, so wonder, can i expect any issues ?
How important is MAP sensor used for barometric correction, how big difference can it make?
How good are standard corrections for VE and IGN ?

Thanks

[rob@vems.co.uk]

Cold start is a big issue as temp drops below zero.
MAP is relatively important, but many cars run with plain AlphaN without barometric correction, you do after all have wideband feedback which will ensure that fuelling is pretty close to spot on except all but high RPMs

[uzelac]

Praxis agree .
Tried to drive a bit today, and expect for small problems with keeping warmup phase on some CLT temperatures, pretty much all worked fine. To my suprise, cranking works perfect, afterstart also. Warmup... it's obvius i need better CLT calibration and Warmup enrichment curve.

MAP sensor is still on ToDo list, but it looks there is no reason to hurry, 4AGE worked just fine in -5 degrees today.

[uzelac]

Regarding, wideband, it's not working OK while idleing.
It shows AFR 20+ while engine idles.
With minor bliping of throttle lambda heads to <1 range.
As TPS returns to 0-1% lambda goes beyond 1.29.

Still, exhaust smells rich, not pig rich but definetly rich.