Setting up for semi open loop

[jfclubby]

Hi guys, Ive been looking for a post that I seen a few months ago on how to set up for semi open loop but can't find it. I'm running COS5 OLSD and wanting to go semi open loop SD with my LS1, Can someone please tell me what tables to change to set it up?

Regards James.

[5.7ute]

With the custom OS anywhere your command air fuel ratio is equal to stoich will give you semi open loop fuelling.

[jfclubby]

Thanks 5.7 ute, Can you have a look at my tune that I just set up and tell me if this will run semi open loop.

Regards James.

[5.7ute]

James. You still have LTFT & closed loop enabled. To run semi open loop you will need to disable these
B4205 to 140 degC
B3801 to disable.(not too sure if this is necessary when B4205 is set at 140)
With that cam you may not want to command stoich in your idle cells as overlap can cause unburnt fuel to mess with your o2 sensors. Your idle could end up pig rich because of this.

[jfclubby]

So do you think I would be better setting my idle cells in B3647 to something like 15.5-16.0 to reduce the chance of the rich idle, Then do the auto ve again to dial that in (I have wondered weather it might be very rich at idle becuse you can smell heaps of fuel) I will also make the changes to B4205,B3801 as you have said. Just so i can understand what these changes will do,
When you set B4205 to max does this mean closed loop fueling won't happen(no LTFT) so the pcm relies on the ve table to be dialed in spot on?

Also while i'm on the topic of COS is there a way to set up a map collecting data to fill A0014(VE multiplier based on intake temp) once the ve is done .IAT's get crazy in the tropicsFinding it hard to get consistant fueling after auto ve because of the dramatic changes in intake temp. Hoping that this table can help.

Regards James.

[5.7ute]

So do you think I would be better setting my idle cells in B3647 to something like 15.5-16.0 to reduce the chance of the rich idle, Then do the auto ve again to dial that in (I have wondered weather it might be very rich at idle becuse you can smell heaps of fuel) I will also make the changes to B4205,B3801 as you have said. Just so i can understand what these changes will do,

First thing you need to do is dial in your ve table to a set intake temp. Set the unenriched areas in B3647 to 14.5 to 1 afr & make sure closed loop is disabled. Set A0014 to 1.00 across the board. Do all your logging at a similar time to keep conditions constant & filter out any intake temps that stray from your benchmark as well as your standard filter set. Eg if your iat is consistantly at 26 deg use this as your benchmark & filter out anything that strays from this.
Once your VE table is dialled in use the Bidi controls in the scantool to find what commanded AFR your car likes to idle at. Use this in the idle cells of B3647. Take note that you can only command as low as B3607 so this may need to be changed.

When you set B4205 to max does this mean closed loop fueling won't happen(no LTFT) so the pcm relies on the ve table to be dialed in spot on?

Correct. Maxing this value will prevent closed loop so there will be no STFT or LTFT. (unless in the case of a custom OS where commanding stoich will cause STFT to occur)

Also while i'm on the topic of COS is there a way to set up a map collecting data to fill A0014(VE multiplier based on intake temp) once the ve is done .IAT's get crazy in the tropicsFinding it hard to get consistant fueling after auto ve because of the dramatic changes in intake temp. Hoping that this table can help.

Regards James.

Yes you can make a map of A0014 & copy, paste & multiply the BEN value to dial in this table. By dialling in the autoVE to a set IAT temp any variation to fuelling can be roughly attributed to the different IAT.
A word of warning though. An incorrect IAT reading from a heatsoaked sensor will make this job difficult. There will be a lot of trial & error to get this close.
If you cant work out how to make the necessary maps PM me your email addy & I will send them through.
Cheers Mick.

[jfclubby]

Thanks Mick, I think i worked out the map to fill the A0014. My row in the map will be named IAT and contain the following lables ,-40,-30,-20,-10,0,10,20,30,40,50,60,70,80,90,100,110,120,130,14 0, and the column will be named BEN_PLX1 does that sound right? Also i'm looking at one of Nathan Higgins new carbon fibre OTR's they are said to be excellent to stop heat soak and also look shit hot under the hood! This would be 100 times better than the GTS mafless intake i've been using! Anyhow I will go and lean the idle with bidi controls and see what happens.

Also when i do the auto ve with B3647 set to 14.5:1 and get that dialed in, Then when i find that happy idle fueling and command that mixture in the idle cells of B3647 do i need to auto ve again or will it trim fueling to get my leaner idle? (might be silly question but still learning).

Regards James.

[5.7ute]

James, I have column as rpm with col labels as ,value(dont forget the comma). Data will be your wideband BEN_PLX1.
As for redoing AutoVE when changing commanded fuel the answer is no, it should not be necessary if the rest of the tune is correct. Unfortunately the autoVE process relies on correctly modelled injectors so you should ensure this is correct before attempting the autove process. Fuel pressure affects the IFR as well so checking (preferrably logging) fuel pressure is a necessary step before autoVE.
Have a look at Marcin's (Redhardsupras) blog. There is a wealth of information in there.
Also I do believe there is a few Efilive users in the Mackay area. It might be worth tracking them down to bounce a bit of info around.
Cheers Mick

[jfclubby]

Hi Mick, I just got home from doing three 40min logs, auto ve. I filtered out anything that was over 35 Deg. Ambiant was 28 and when driving i was seeing intake temps of 30-35 so i got rid of anything over that.(badly need that OTR) So with the paste and multiply at intake temps between 30-35 my ben's in auto ve are now 1.0-1.01 so i think i've got it close enough for now.
Next is to sort that idle fueling out, i've set B3647 to 15.5 in idle cells and it runs ok so ill see what happens. So Mick can i set the rest of B3647 back to stoich and let it STFT?

As for coming across efilive users in Mackay i only know of ntae and he is very helpful. It would be good to find more to share ideas and info.

I just love using this forum, So many switched on people with years of experiance.

[5.7ute]

Once you are happy with your BEN's you will be fine to return the rest of the unenriched cells to stoich for semi open loop. Dont forget that B3607 limits how lean you can command at idle so this will need to be changed.
This is definately a great site full of helpfull & highly knowledgable people. There is no way I would have attempted to learn how to tune without their support.