Tuning after a pro tune
#11
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Joined: Feb 2013
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From: Somewhere north of 285, south of 985.
Short version (if you're logging the right stuff):
If your fuel trims are +, then the pcm is adding fuel.
If your fuel trims are -, then the pcm is pulling fuel.
In your ve table, take the error graph (your log in the scanner), select all, go to your ve table, right click, paste - multiply by %. Then select all in your ve table and click the smooth button, one time. Rinse and repeat until it's as close to 0 as you can get. +-1 is typically acceptable.
For WOT, you really need a WB. In theory, once the ve table is right, then you should be able to command 12.8-.9 (whatever your preferred WOT afr is) in the PE table and it'll be right, in theory.
If your fuel trims are +, then the pcm is adding fuel.
If your fuel trims are -, then the pcm is pulling fuel.
In your ve table, take the error graph (your log in the scanner), select all, go to your ve table, right click, paste - multiply by %. Then select all in your ve table and click the smooth button, one time. Rinse and repeat until it's as close to 0 as you can get. +-1 is typically acceptable.
For WOT, you really need a WB. In theory, once the ve table is right, then you should be able to command 12.8-.9 (whatever your preferred WOT afr is) in the PE table and it'll be right, in theory.
#12
I know that fuel error is the correction that the PCM is making to the fueling against the ve estimates and maf. Correcting for the errors gets the fueling corrected that way when you command and afr target the PCM will go right to that target. At least that's the correct way to tune.
What sensors do I tell the scanner to look at? I just downloaded hp 3.2 and I'm assuming the "graph" feature is what the "histogram" is so I need to know what values and sensors to define to be logged for VE fuel error.
Sorry - it's just as soon as I think I understand the software I read something that completely throws me off what I thought I knew.
Thanks for dealing with a noob
#13
Joined: Jan 2006
Posts: 16,282
Likes: 438
From: Huntsville, AL
The sensors we use for fueling error are oxygen sensors. Your truck comes with 2 narrowband oxygen sensors, but they are only good when you target stoich afr. A wideband is needed if you really want to know what the AFR is at something other than stoich.
For VE you need to plot the average of those sensor trims on a graph of manifold air pressure vs engine speed. For the MAF you plot against MAF frequency.
For VE you need to plot the average of those sensor trims on a graph of manifold air pressure vs engine speed. For the MAF you plot against MAF frequency.
#14
Thanks Atomic - Wideband was delivered on Saturday and it'll be installed this week. I'm trying to figure out how to put the output of the wideband into pin 55 for EGR and have it read AFR from the voltage of the wideband.
Are those graphs already setup or do I have to I have manually create them? I've seen some people ask for config files but I also want to learn how to make them myself
Are those graphs already setup or do I have to I have manually create them? I've seen some people ask for config files but I also want to learn how to make them myself
#16
Ok - I had some success over the weekend, and some challenges.
1. Success - PLX WB installed and working correctly on B1 which is supposedly the "lean" bank.
2. Integrated it into the stock PCM EGR pin 55 using said PID calculation.
3. Successfully got truck into Speed Density mode to tune for AFR correction for VE table.
4. Did some logs and calibrated the VE table a little bit - still needs work in a couple areas. The laptop I'm using is ancient and battery life is dismal so it is limiting me from really getting good logs.
5. Challenge, couldn't figure out how to calibrate MAF. I thought I had the correct graphs/Histograms created but they all came up zero. - Maybe this is because the pro tuner did this already?
6. How do I make the EGR Sensor read AFR 14.7? In my logs it only reads volts so I'm trying to make it read AFR so that I can check for gauge offset.
Thanks!
1. Success - PLX WB installed and working correctly on B1 which is supposedly the "lean" bank.
2. Integrated it into the stock PCM EGR pin 55 using said PID calculation.
3. Successfully got truck into Speed Density mode to tune for AFR correction for VE table.
4. Did some logs and calibrated the VE table a little bit - still needs work in a couple areas. The laptop I'm using is ancient and battery life is dismal so it is limiting me from really getting good logs.
5. Challenge, couldn't figure out how to calibrate MAF. I thought I had the correct graphs/Histograms created but they all came up zero. - Maybe this is because the pro tuner did this already?
6. How do I make the EGR Sensor read AFR 14.7? In my logs it only reads volts so I'm trying to make it read AFR so that I can check for gauge offset.
Thanks!
#17
Joined: Jan 2006
Posts: 16,282
Likes: 438
From: Huntsville, AL
5. The MAF is not used in speed density mode. If you still have it installed, you want to plot trims or afr error vs maf frequency.
6. You need the output of the wideband sensor to figure out the equation, or sometimes the manual tells you directly. The value at 0 volts will be the intercept, and the slope will be [voltage * (AFR_range/voltage_range)].
6. You need the output of the wideband sensor to figure out the equation, or sometimes the manual tells you directly. The value at 0 volts will be the intercept, and the slope will be [voltage * (AFR_range/voltage_range)].
#18
5. My tuner likes to use the MAF until it's maxed out - he said it provides better and more accurate control. So I would plot the same AFR error I created for my wideband for VE tuning and plot that against Maf frequency? I'm pretty sure I did that and got Zero's across the board
6. I know the output of the Wideband - I just don't know how to change the sensor to display AFR in the channels and the chart vs time. Can I change the equation for the pid to display AFR? When I right click on the egr sensor channel it only gives display units Volts or mV
And I know you are trying to help Atomic, it is much appreciated. But I'm just a knuckle dragging mouth breather over here - sometimes your language is way over my head
6. I know the output of the Wideband - I just don't know how to change the sensor to display AFR in the channels and the chart vs time. Can I change the equation for the pid to display AFR? When I right click on the egr sensor channel it only gives display units Volts or mV
And I know you are trying to help Atomic, it is much appreciated. But I'm just a knuckle dragging mouth breather over here - sometimes your language is way over my head
#19
5. My tuner likes to use the MAF until it's maxed out - he said it provides better and more accurate control. So I would plot the same AFR error I created for my wideband for VE tuning and plot that against Maf frequency? I'm pretty sure I did that and got Zero's across the board
#20
Again - I think I'm hopeless. I know what all that stuff means, I just don't know how to make HP tuners do that.
I'll keep farting with it - it's just frustrating because I only get maybe 30min of battery on my laptop before it dies, so I'm trying to figure it out before getting in the truck.
Couple that with 113deg temps we are having right now, so you can see I'm trying to minimize my time in the truck as much as possible.
I am making progress, but each time I think I know what I think I should do - HP Tuners slaps me across the face with a trout.
I'll keep farting with it - it's just frustrating because I only get maybe 30min of battery on my laptop before it dies, so I'm trying to figure it out before getting in the truck.
Couple that with 113deg temps we are having right now, so you can see I'm trying to minimize my time in the truck as much as possible.
I am making progress, but each time I think I know what I think I should do - HP Tuners slaps me across the face with a trout.







