VVE Help

[etmotorsports]

New at tuning vve cannot seem to get this to be stable at idle. Here are the logs i have followed swingtan vve setup guide.
VVE_tun010.efi

VVE_010.tun

[Taz]

The E38 / E67 idle tuning thread below is long, but very comprehensive. Just pointing you in the right direction - I work primarily with the Gen III - definitely not a Gen IV expert.

http://forum.efilive.com/showthread....38-idle-tuning


Regards,
Taz

[etmotorsports]

i have seen the idle tuning but i was hoping to get it more consistent 1st with vve tuning, i can get it to idle at 18:1 or around 12:1 and maintain that a/f but no where in between. Guess i need to see if there is anything in there

[swingtan]

Some specs on the motor and vehicle would help. Auto /Maual, cam, intake, exhaust etc.

Simon.

[etmotorsports]

2010 Camaro automatic, has cam not sure what size around .58-.59 lift, single 72mm turbo, lsx intake, zr1 map sensor, was tuned off maf trying to get it to drive better and be more consistent a/f

[swingtan]

Well, that explains the VVE shape a little. try the following...

• Reset the ECM between idle changes. Remember that idle and fuel trims stay between flashes so you need to clear any learned data.
• Always log Inlet Valve Temp! Always!
• B1845: To reduce the effects of learned idle data, set all cells from -64 to +64 RPM to "0"
• B1650: reduce by 25%
• B1829: set all cells under 800rpm to 9gm/Sec. set them all to the same as the 800rpm cell. You can even increase the values a little to help with the idle correction.
• B5104: increase idle spark to around 21' to 23'
• B5128 to B5131 look all wrong. Spark has a much bigger influence on idle control than throttle. These tables are zeroed up to 96RPM error which is bad! Actually, it's probably these tables causing most of the problem. As a quick fix, linear fill from 0 to 112 RPM with the current tables, then fine tune. try this first and see how it goes.
• B1821: increase the minimum idle speed. This helps to get the idle right, then once it's stable, lower it and fine tune.

See how that helps.

Simon.

[etmotorsports]

Thank you for the advice try all of that.

I have another stupid question does the higher the # in the vve table mean more fuel? From what i can tell it does but not sure.

[ringram]

Yep basically, but the number is fairly meaningless in itself

[JAY4SPEED]

Well, that explains the VVE shape a little. try the following...

• Reset the ECM between idle changes. Remember that idle and fuel trims stay between flashes so you need to clear any learned data.
• Always log Inlet Valve Temp! Always!
• B1845: To reduce the effects of learned idle data, set all cells from -64 to +64 RPM to "0"
• B1650: reduce by 25%
• B1829: set all cells under 800rpm to 9gm/Sec. set them all to the same as the 800rpm cell. You can even increase the values a little to help with the idle correction.
• B5104: increase idle spark to around 21' to 23'
• B5128 to B5131 look all wrong. Spark has a much bigger influence on idle control than throttle. These tables are zeroed up to 96RPM error which is bad! Actually, it's probably these tables causing most of the problem. As a quick fix, linear fill from 0 to 112 RPM with the current tables, then fine tune. try this first and see how it goes.
• B1821: increase the minimum idle speed. This helps to get the idle right, then once it's stable, lower it and fine tune.

See how that helps.

Simon.

Simon, by "reset the ECM" do you mean to clear trims via DVT? Does that clear idle trims as well as regular trims? Or is there another method of resetting the ECM that you are referring to?

[etmotorsports]

I have another question if someone know the answer or can help me out. When i paste and multiply the ben map data it increase the or decreased the vve table in those spots needed but when you generate and make vve it reduces those by a drastic amount and sometimes it even makes the the opposite of what they "should be". IE if a cell is at 1566 and the data has a .91 then you get 1425 there but after generation it is only 1550 or so and i have even seen where it would go the opposite.

I know about averageing around the cell and all that does help but it seems the next log it needs another .91 or even less .85. I am wondereing if there is something i am skiping?