Lambda

[ancientcitycustoms]

I know i ask some pretty naive questions but this one just doesn't make sense. Please don't flame as i am just trying to understand how the table controls the truck.
So...
I intentionally made a tune for the 6.7L that would over fuel just to try to figure out Lambda, all for testing purposes.

When i zero out all the Lambda tables, I see zero smoke/light haze.
When i set all Lambda tables to 1.0, it will roll until i let up off the pedal.

From what i understand, Lambda is a ratio that the vehicle uses, in a sense, equalize fuel to air.

This seems backwards to me, 0.0 shouldn't apply any correction while 1.0 would correct.

Is there something i am not taking into consideration?

[RandomEnthusiast]

Diesel is a bit different to gas. I haven't messed with 6.7l. But it sounds like it's correcting to run rich.

[gilgamesh]

I know i ask some pretty naive questions but this one just doesn't make sense. Please don't flame as i am just trying to understand how the table controls the truck.
So...
I intentionally made a tune for the 6.7L that would over fuel just to try to figure out Lambda, all for testing purposes.

When i zero out all the Lambda tables, I see zero smoke/light haze.
When i set all Lambda tables to 1.0, it will roll until i let up off the pedal.

From what i understand, Lambda is a ratio that the vehicle uses, in a sense, equalize fuel to air.

This seems backwards to me, 0.0 shouldn't apply any correction while 1.0 would correct.

Is there something i am not taking into consideration?

What happens if you go higher than 1.0? I understood lambda to be a value less than one is richer and a value greater than 1 is leaner. Which sounds the opposite of what your test results were.

[Rigo_eff1fitty]

Diesel stoichiometric ratio is 15.2 just a tip.

[gilgamesh]

Diesel is a bit different to gas. I haven't messed with 6.7l. But it sounds like it's correcting to run rich.

If you changed the IQ map to open the injectors for longer than necessary for the given amount of fuel in the IQ table could this cause black smoke to occur at lambda 1.0?

[ancientcitycustoms]

What happens if you go higher than 1.0? I understood lambda to be a value less than one is richer and a value greater than 1 is leaner. Which sounds the opposite of what your test results were.

I was under the same impression yet it does not make sense. Ive been trying to data log but i am getting very inaccurate numbers when using vcm scanner. I am wanting to try 2.0+ just to see how the truck reacts. From what i am getting at so far, as i was able to try .01-.99, .00 might make the truck default to a certain setting because as long as there is a digit, it tends to work as previously thought. .01 has less correction while .99 has a greater correction to the amount of fuel being delivered when there isn't sufficient air to compensate.

[gilgamesh]

ok, that sounds like appropriate behavior. I can see how 0's could have a funny effect on this as an input. They probably don't have a whole lot of error checking for "bogus" values in the lookup tables. I think they probably expect those to be rather predictable.

[gilgamesh]

Did you ever happen to try 2.0+? I'm curious how it behaved.

[ancientcitycustoms]

Did you ever happen to try 2.0+? I'm curious how it behaved.

I have not yet. Although i finally got around to data logging to show that the truck did not de fuel when 0.0 lambda was entered at a WOT run. I have been messing around narrowing down which timing maps are used with and without emissions equipment which i will post in the other thread.

[gilgamesh]

Did you ever happen to try 2.0+? I'm curious how it behaved.

I tried lambda 2.0 today it removed all smoke from my pretty heavily modified duration map with dual fuel. I then found that 1.5 works pretty well for most of the map and I needed a slight boost to 1.75 in a specific RPM range and fuel qty.