VEMS Idle settings without Idle Valve using Ignition

[A80Avant]

i see.
so you guys with the vems,can you guarentee that the car will idle fine on cold and warm conditions?
can you also guarentee that it wont stall or have problems while the A/C is working?

If so,how is it done?cause up to now,the problem with the VEMS is that it has an unstable idle making it jump up and down until the car is on operating temp,and to be honest i dont like to be told that this is the downside of an aftermarket ECU.These things are top range and are supposed to be able to produce even better results than old stuff,like motronic and can be programmed for part throttle as well,not only WOT and off.

SO can the VEMS provide me with an identical feel as the motronic? I can cope with not using the tank display or the fault codes(besides,i can just connect the motronic back on,and see them)

[a4kquattro]

i see.
so you guys with the vems,can you guarentee that the car will idle fine on cold and warm conditions?
can you also guarentee that it wont stall or have problems while the A/C is working?

All the cars I tune on VEMS I actually dont use the idle valve. All attempts to tune using the valve have resulted in oscillations I find unacceptable, so instead I use the rather nice ignition-based idle control feature in the VEMS software that allows for very good and very smooth idle control by the computer rapidly altering the ignition timing to produce a nice smooth steady idle.

With this configuration I find the idle works perfect without ac, with ac on idle drops about 150rpm (which can cause the car to stumble if the static idle is set to around 900rpm, so instead I configure my customer cars to idle static at around 1050-1100 by opening up the idle screw a bit and all is well, ac or no ac).

[pnanassy]

Yepp.thats true,but we also managed to work a 1.8t 8v quattro with IAC valve acceptably.Not even near to stock tough.

But its an evolving system,more requests generate more attention from the programmers.Because its mainly a software related issue.Better algorithms would work much better.

IAC tuning is also very time consuming,and very small changes in conditions can have a great affect on it.I spent about 30-40 hours to develop mine on Motec M600,and also the VEMS equipped car needed serious amount of care.

Peter

[GazzaG60]

i too dont use the idle valve. found it worked well sometimes and then others not. it would stall. basically i do what mark to an extent.

ican find a good enough for me idle without it so im non too fussed. not messed with the ignition based idle yet. will have a look but to be honest im happy with idle

[gnutz2]

All the cars I tune on VEMS I actually dont use the idle valve. All attempts to tune using the valve have resulted in oscillations I find unacceptable, so instead I use the rather nice ignition-based idle control feature in the VEMS software that allows for very good and very smooth idle control by the computer rapidly altering the ignition timing to produce a nice smooth steady idle.

With this configuration I find the idle works perfect without ac, with ac on idle drops about 150rpm (which can cause the car to stumble if the static idle is set to around 900rpm, so instead I configure my customer cars to idle static at around 1050-1100 by opening up the idle screw a bit and all is well, ac or no ac).

I found the same on my dta ecu.

I now use the ignition advance to control the idle, TBH i dont know what the problem everyone is talking about. most ecu`s can idle fine as long as they have battery voltage correction.

Even if you just let it idle on the TB screw.

[Billman]

According to Marcel the next FW version for VEMS will have Battery voltage correction (it should be available but something holds back the testing).

@A4KQuattro
Can you give us your idle settings. I use both now but i still have problem with oscillations now and then.

Thanks

[a4kquattro]

Sure, here are my settings. Under Extras->Idle Settings Advanced/PID:

Ignition Based Idle Control
Active = Enabled
Advance Change max advance (deg) = 10
Advance Change max retard (deg) = 10
Advance rate of change (deg/256rpm) = 10
Threshold for activating IAC (deg) = 10.5

PID settings below dont matter, because on the main idle settings page I disable the idle valve via:

Iac Hardware Setup:
Idle solenoid channel = Disabled

[Jamo]

Moved to aftermarket ECU section

[20vQC]

wow...nice info

[gnutz2]

DTA does have battery voltage correction and it helps get a steady idle.

[20vQC]

Now my idle works absolutely great!!! It's made a huuuge difference with the ignition controlling it!

[K7ERG]

Not using the idle control valve either.

Idles good.

[a4kquattro]

Now my idle works absolutely great!!! It's made a huuuge difference with the ignition controlling it!

glad to hear it

[Billman]

@Offtopic

now that we are here many people with VEMS, does anyone had luck with the Knock Sensing?

[Billman]

I did it also now with the Solenoid turned off but i set it to 850 RPM; when cold it stays stable to 850 when warm it goes up and stays at 1000 RPM. Why?

Please comment on the knock thing also...

thanks