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

[[email protected]]

You may be way past the point where the wideband reads correctly - can you get the idle to around 0.95?  It should idle cleanly at that.
What sort of PWs are you seeing at idle?

[jrussell]

How important is MAP sensor used for barometric correction, how big difference can it make?

Not important at all unless you drive up a mountain often and are non-turbo.

The ECU reads the MAP sensor to get the barometric pressure before the engine cranks. That way a dedicated barometric sensor isn't needed. Unless the pressure (altitude) changes drastically (100's of meters) it's going to be just fine.

[uzelac]

Barometric correction is used only once before crank ? And not while engine is running ?
Seems like wideband alone will have to be enough :).

I can't get idle at 0.95, if i add fuel engine revs up. Maybe i have too much air going through my intake...
IGN is set to 15, stock 4AGE idles around 16.

BTW. I don't use any Idle control.

[[email protected]]

You have too much air, and you're leaning out the fuel to get the thing to idle - I bet it sounds a rough as hell on idle.
Put more fuel in let the revs rise up to 2000-2500rpm, close down the throttle plates so that the engine speed is closer to idle, then repeat this process until the warm engine is idling at the right speed with lambda close to 1.0
This will probably result in you having poor starting behaviour, but that can be tuned out easily enough.
Getting some form of IACV in there is never a bad idea...

[uzelac]

Sounds great, will give it a try but not sure if it can be done.
My ITB's are pretty much closed... i guess it's time to check for leaks in intake.
And IACV.... i don't really need that good idle, this ain't daily driver, maybe when more important things are sold. As MAP and VSS...

[[email protected]]

yes - you need a leak free intake.

[uzelac]

BTW.

I constantly get validation errors on loading config:
It says:

Following symbols have invalid values
H2D7
H2D6
H2D5
H2D4

In earlier versions it looked the same except VemsTune directed me to:
Base Setup: Ignition Outputs dual.

Now i get only "invalid values".
I guess these are leftovers from some earlier VemsTune versions conflicting with  mine 4x COP/Wasted spark/DualOutput.

Can i fix it in config somewhere or is it an issue with VemsTune? I use most recent VT.

Here is my config:
https://docs.google.com/open?id=0B6eLVO1tr19nYzRmYmEyNWEtNWU1Yy00OWY2LWFjMWMtNjNmYTk4YzZhOGQ3

[GintsK]

It is pretty easy to solve: temporary configure 8 ignition outputs and then edit four invalid ones to any other outputs. Then go back to 4 outputs.

Gints

[uzelac]

What sort of PWs are you seeing at idle?

Around 2.7msec.
250cc injectors LowZ (now with TS diode).

[uzelac]

What is a better option for a IACV, that default is closed or partially open ?
I found some Bosch IACV, it's open by default.

How will it work with VEMS default settings ? Is setting up an IACV pain in the ass or should be pretty simple ?

Thanks

[[email protected]]

Difficulty levels depend on your throttle bodies - stock bodies have a nice joint air feed for the IACV.

[uzelac]

Installation shouldn't be a problem. Drilling nipples is easy, what bothers me is setting up :).

[[email protected]]

I think the late Rover Mini that had EFI used a solenoid to open the butterfly, if this is a thought...
Most if not all IACVs fail open - if they failed closed then people would have problems starting their cars, as it fails open they'll notice a high idle RPM.
Fitting BOSCH parts has never been a bad idea.

[uzelac]

Btw.

found the leak in intake, of course :).
Intake manifold is going to be flattened at the shop, after that i hope there won't be more problems with idle.
Maybe even WBO2 will show ~1 lambra at idle :)

[uzelac]

Got rid of the leaks but i can't achive good lambda at idle.
It's either these ITB's can't close enough, or i have problems with WBO position or sensor itself.
It works fine while running, but at idle it goes above 1.29 :/