VEMS 1.8t 630cc coldstart problems

by **88a5tq** » Wed Jun 17, 2015 10:50 pm

I did it accidentally on mine lol

by **Marc** » Wed Jun 17, 2015 11:05 pm

ChrisAudi80 wrote:Kevin Black at Lugtronic apparently knows how to implement good IAC control on VEMS. However, it is most likely a closely guarded secret.

I've seen his tunes. no secrets and no major differences to whats already been discussed.

by **Urtorsen** » Tue Jun 23, 2015 4:19 am

It works.....because I've used it for almost all of winter from sub zero to warmup, so I think with some effort (from the brains behind VEMS) I think they could get it perfect....enough to be steady,handle the AC, warmup and not interfere with the throttle feel so much. I'm still trying to get a hold of him to see if there is something special lol but no response.
Have the bosch 2 wire ISV now so should be much much better

by **Urtorsen** » Mon Dec 28, 2015 5:26 am

Well it's been a while but had to tear into the car to replace the trans, as 3rd gear was horrible and I think a bad fork.that plus steering rack leak, and other lil bits nagging me. I installed w/meth injection kit, wired in provisions for the E85 flex sensor and generally tidied up the entire loom and powder coated a few things.
After all the trouble with the idle ...last winter coldstarts and the ac during the summer.... I found an old Volvo 2 wire at the breakers yard and wired it into the loom too, really makes idle control a hell of a lot easier. I'm still only fine tuning the PID but already loving it and it doesn't interfere with driving like the integrated idle motor in the AEB throttle body .

by **Urtorsen** » Mon Dec 28, 2015 9:44 pm

Well it blew past the seal on the Volvo one at 25psi. Just put in the stronger looking Bosch 2wire

by **Urtorsen** » Thu Dec 31, 2015 11:43 am

Ok I put in the vw idle valve and no DC will close it. I've read here that you guys run 30% to close the valve but mine never closes more than when disconnected. I'm leaking boost past it so I need the valve that closes fully at 30%dc that i read about you guys using

by **Urtorsen** » Thu Dec 31, 2015 11:04 pm

Nevermind, just realized they never close fully, I vented the input side to after the air filter, just have to install it the right way from the charge pipe to IM instead.

by **ChrisAudi80** » Sun Apr 17, 2016 4:01 am

Just wondering how you are doing with this. Any chance you can post up your 1.8t AEB 630cc VEMS config? Did you switch to E85?

I am going to install my VEMS unit and harness soon. Probably next month sometime. I am still stock turbo, but I am hoping your config will be usable for mine. I do plan to swap in a larger turbo in the future.

My ECU and harness also came from KB.

by **ChrisAudi80** » Wed Feb 22, 2017 4:43 am

Wonder where OP went...

Anyway, I am controlling the AEB IAC with VEMS now. Its a little better than no IAC. Took some fiddling. Followed this thread: http://forums.vwvortex.com/showthread.p ... S-iac-help

I did like Prof315 said: " I wired up the idle motor part of the throttle (pins 1 and 2) backwards so pin 1 is PWM control and pin 2 is switched 12V. Then I set the MS3 PWM idle control to run inverted. I'm running the valve at 200hz and the DC range is roughly from 40% to 100%. "

Have to play with DC a little and still dialling it in. Not so sure my TB is 100% anymore. Might have not open it up and spray a little WD40 in there.
Can actually get idle with AC on to go to 800rpm!

by **beemer832** » Wed Feb 22, 2017 3:21 pm

ChrisAudi80 wrote:Wonder where OP went...

Anyway, I am controlling the AEB IAC with VEMS now. Its a little better than no IAC. Took some fiddling. Followed this thread: http://forums.vwvortex.com/showthread.p ... S-iac-help

I did like Prof315 said: " I wired up the idle motor part of the throttle (pins 1 and 2) backwards so pin 1 is PWM control and pin 2 is switched 12V. Then I set the MS3 PWM idle control to run inverted. I'm running the valve at 200hz and the DC range is roughly from 40% to 100%. "

Have to play with DC a little and still dialling it in. Not so sure my TB is 100% anymore. Might have not open it up and spray a little WD40 in there.
Can actually get idle with AC on to go to 800rpm!

I found this discussion after a quick google search. I just installed a VEMS system on my AEB 1.8t and am having idling issues like was mentioned here. I am very new to the tuning side of things and have EFIExpress helping me, but I'd also like to learn on my own.

So I am guessing that my idle issue, which seems to be fine when the car starts, but as soon as you blip the throttle, and it starts to come back down, the car will not idel. When you're driving you must rest your foot on the accelerator at a stop or it will stall. If it stalls, you need to tap the throttle a few times to get it come on.

I did the idle enrichment curve already and I am between .90 and .95 lambda so I assume I am good there.

If this seems to be the issue, I will start following the writeup that was linked and see if that fixes my issue. Thanks!
-josh

by **ChrisAudi80** » Wed Feb 22, 2017 9:13 pm

beemer832 wrote:
ChrisAudi80 wrote:Wonder where OP went...

Anyway, I am controlling the AEB IAC with VEMS now. Its a little better than no IAC. Took some fiddling. Followed this thread: http://forums.vwvortex.com/showthread.p ... S-iac-help

I did like Prof315 said: " I wired up the idle motor part of the throttle (pins 1 and 2) backwards so pin 1 is PWM control and pin 2 is switched 12V. Then I set the MS3 PWM idle control to run inverted. I'm running the valve at 200hz and the DC range is roughly from 40% to 100%. "

Have to play with DC a little and still dialling it in. Not so sure my TB is 100% anymore. Might have not open it up and spray a little WD40 in there.
Can actually get idle with AC on to go to 800rpm!

I found this discussion after a quick google search. I just installed a VEMS system on my AEB 1.8t and am having idling issues like was mentioned here. I am very new to the tuning side of things and have EFIExpress helping me, but I'd also like to learn on my own.

So I am guessing that my idle issue, which seems to be fine when the car starts, but as soon as you blip the throttle, and it starts to come back down, the car will not idel. When you're driving you must rest your foot on the accelerator at a stop or it will stall. If it stalls, you need to tap the throttle a few times to get it come on.

I did the idle enrichment curve already and I am between .90 and .95 lambda so I assume I am good there.

If this seems to be the issue, I will start following the writeup that was linked and see if that fixes my issue. Thanks!
-josh

Are you having this issue with AC on or off? I am still dialing this in. Just know that VEMS control of the IAC is not ideal, but better than nothing.
See attached my current config.

by **beemer832** » Thu Feb 23, 2017 12:01 pm

I haven't even tested the AC being on yet. It has this issue just trying to idle with no load. I will take a look at your config and see how mine compares. Thanks!
-josh

by **ChrisAudi80** » Fri Feb 24, 2017 4:11 am

beemer832 wrote:I haven't even tested the AC being on yet. It has this issue just trying to idle with no load. I will take a look at your config and see how mine compares. Thanks!
-josh

Sure, just keep in mind that I run Deka 630cc injectors at 2.5bar on E85.

by **beemer832** » Wed Mar 08, 2017 12:02 am

Still not idling as ideal as I'd like. I guess I was spoiled with the old Apr tune.

Anyway, I am running 630cc injectors but normal 91 octane. Marc has a few more tweaks to go still but I am hoping to have a nice healthy idle soon.

-josh

by **Urtorsen** » Mon Apr 10, 2017 12:47 pm

Sorry haven't been paying much attention to the forums most weeks.
That's great to hear that works, I would've been afraid to try that incase I popped something lol.
I could get it to work but to make it driveable like the Bosch 2 wire independent isv valve didn't happen, has either of you tried the higher freq available now?? It's like 400hz or higher , I forget ....Marc has my ECU right now though and my blocks being machined so I can't tell .
I just didn't like the rev hang in high duty in hot weather and the AC on in traffic, coming to a stop it wouldn't smooth out quick enough , after countless tries of adjusting the PID. .
i got all of that to work on the isv valve no problem, I'm probably gonna go back to the throttle body idle motor when I get it running again. I can try a little stepper idle valve after that if it doesn't work.

by **ChrisAudi80** » Tue Apr 11, 2017 10:14 pm

Urtorsen wrote:Sorry haven't been paying much attention to the forums most weeks.
That's great to hear that works, I would've been afraid to try that incase I popped something lol.
I could get it to work but to make it driveable like the Bosch 2 wire independent isv valve didn't happen, has either of you tried the higher freq available now?? It's like 400hz or higher , I forget ....Marc has my ECU right now though and my blocks being machined so I can't tell .
I just didn't like the rev hang in high duty in hot weather and the AC on in traffic, coming to a stop it wouldn't smooth out quick enough , after countless tries of adjusting the PID. .
i got all of that to work on the isv valve no problem, I'm probably gonna go back to the throttle body idle motor when I get it running again. I can try a little stepper idle valve after that if it doesn't work.

I have gotten the TB IAC to work somewhat. I don't really use the PID, mainly just DC. I have an old VEMS ECU, so cannot upgrade to 1.2.38 yet. I need some kind of bootloader to go from n to uhex.

It's stable @775-800 when engine warm. AC off it idles at 1000-1200, which I don't mind. AC is on most of the time.