Speed density setup for editor and scanner

[mjc79]

:::Updated info in comment #4:::


I am having a hard time trying to set up the editor and scanner so i can tune the VE section on my 02 Tahoe. Everywhere i look seems to have different methods in doing it but its not working for me for some reason. Im sure i missed something somewhere or its just plain bad info.

Thanks

Michael

[mjc79]

Anyone have a good tutorial to use? Tried Goat Rope Garage, Chopper Doc and even the the methods in the stickies here and NOTHING works for me to tune the VE part. It either runs like crap with one method or it does'nt populate the VE table on the scanner with another method. Trying to save hundreds of dollars doing it myself but it seems no ones method works for me

[Matt Vardaman]

Post your tune file .hpt and log file .hpl. We can help by looking at your graphs. There are also some channels lists, and graphs pre set up if you will use the search function of the forum.

[mjc79]

went back with Goat Rope Garages method since it would run, idled a little rough, but ran. Current tune and a small log posted below

[kevin87turbot]

With that combo, you can take 20% fuel from 0-800 rpm, then take 10% from 1200-1600 rpm before you get started. That'll get it in the ballpark, then start tuning from there.

[mjc79]

With that combo, you can take 20% fuel from 0-800 rpm, then take 10% from 1200-1600 rpm before you get started. That'll get it in the ballpark, then start tuning from there.

Thank you i'll try that and see what happens. I had made a longer drive around log also but the laptop shut off and cut the connection to the scanner and wasn't able to save it in time. Downloaded everything to my new laptop so I'll get a new log up here in a little while.

[mjc79]

Been having problems with everything tune related so I started back over again and need someone to look over this tune to make sure its right for a VE tune to start with

[[email protected]]

so i have a question for you do you just need a way to ve log or i the truck not running?

i looked on my computer and the ve correction is there all you do is copy the chart for ltft then paste specials in the ve now if nothing changes the its because you are not in sd mode

i also noticed no tps reading =not good

[mjc79]

The vehicle has been running since Oct. 2020 but I can't find any updated editor or scanner instructions on how to set up speed density tuning, maf tuning or base running airflow tuning that actually works. All the info in the stickies is outdated and does not work with the newer 4.1 software versions. One person says do this and that and another person says something totally different. Even tried Goat Ropes methods and it would run decent, but would not populate the graph in the scanner like it's supposed to. Since I tried fixing and changing stuff around in the scanner to work like they had, it's all jacked up now and doesn't work right so I'm at a dead end so to speak. The only thing I found on this site that worked somewhat was setting the base idle airflow, but it wouldn't log idle trims in the graph so I haven't had a true base idle tune set up for 2 years. Tried searching so I could fix it, but nothing seemed to work. Or I could have been sold defective hardware since the beginning. The USB cable hasn't worked right out of the box. You have to either move the cable around or unplug and plug it back in to write a tune. Thought it was the old laptop I previously used, but it does the same thing with the new laptop. Sorry for the long rant just trying to explain everything that's happened since the beginning

[kingtal0n]

Setup wideband input so it will log like this

wbafter-a-day-of-tuning.png

make sure wideband gauge matches scanner recorded values.

Adjust the filters so the same log gives multiple view points. For example Tps > 5% to eliminate all situations with less than 5% throttle from the data. And so forth.

You should wind up with several different logs of the same data, showing different trends for different situations.

Make sure closed loop is disabled. I recommend avoid closed loop all together and focus on tuning the engine manually, fully. When finished if you want closed loop you can re-enable but I never use closed loop or narrowbands because 14.7:1 is not a desirable a/f ratio for any situation.


Before doing any VE map tuning make sure the VE values make sense and that the injector size setup and torque predictions / airflow predictions make sense.
The VE table should flow smoothly like this

latestve.png


No big jumps except near idle sometimes and just off idle sometimes.

Then you simply sit at kitchen table, review logs, and adjust the VE table so that the commanded A/F values match reality. I do this by simply comparing the logged data with the commanded A/F ratio from the scanner at each specific logged cell. Once you hit the cells that make sense you can smooth all around them to adjust the nearby areas that you do not have good logged data for. Rinse and repeat.

Heres a list of generalized target A/F ratios
https://forum.hptuners.com/showthrea...l=1#post678778

[mjc79]

Thanks for that info! Right now i just have the tune loaded that is a modified stock table but maf and speed density settings are set as stock. The only changes i made on the engine side was for injector data and from the previous idle tuning setup to get the base running airflow somewhat dialed in to hold a good idle. VE was never messed with from the stock table because the idle trims graphs would not populate any data in them. Before the scanner settings got all messed up it was running rich at operating temps for the short term fuel trims, now they are lean. I went over the inputs and graph settings on the scanner multiple times and couldn't see why they wouldn't work. Its just odd that i'm having so many problems getting this stuff to work right lol. I bought a new data cable to go from the laptop to the mpvi2 hardware but that didn't change anything. I'm sure something is messed up somewhere with the scanner that i'm not seeing. I'll attach the lastest tune file, the log and the channels and graphs setups. If you need something specific let me know. If nothing works, that's why i'm frustrated lol

Edit: The biggest beef I have right now is not knowing what to start with from as found stock tune. I tried this method -->https://forum.hptuners.com/showthrea...e-(w-pictures) , but could not change it to where the timing matched all 4 tables in the areas it said to change. It idled so rough it shook the whole truck back and forth, so i just set the spark advance idle in park to 2* higher in the idle areas from and that made it idle somewhat smooth. Never touched the stock VE table with that method either. Using Russ Ks methods for the scanner setup is where it would not log short or long term idle trims, the graph would just be blank

[kingtal0n]

DO you know how to tune a distributor advance for mechanical timing? Try to learn that if you don't, understand the centrifugal weight system and implement something similar in your timing profiles. Open and read every single timing related table and try to understand what it says. There are different tables for idle and throttle closed for example that if not tuned to the same timing values as the base timing map e.g. "high octane" the timing won't be stable when you touch the throttle. At idle the timing control feature is very powerful but I would recommend turning it down or nearly eliminating it at first so you can focus on creating a steady idle without the help of timing control feature. This will help you dial airflow and fueling to achieve a steady idle speed. Then you can re-enable and play with the idle timing feature and it will become even more stable. If you rely too heavily on timing idle control feature it will mask other issues with air and fuel this is why I say tone it down for the time being.

I recommend disable the maf for now. I don't see any use for the maf sensor in a performance application. Some people still want to use it though, which I Do not understand, but its up to you I guess. At the end of the day an a/f number on the wideband is all that matters, whether you get it by using MAF or VE doesn't make any difference to the engine.
Maf is very powerful for tuning quickly, it is an easy 'short cut' to take, however it is also very sensitive to perturbations of flow, turbulence, compressor surge, swirl/vorticity, bends in the plumbing, etc... so I just as soon get rid of it.

I recommend turning off closed loop and fuel trims. Disconnect the Narrowband O2 sensors for tuning. Rely only on the wideband and even then only take the wideband as a general result, an average of cylinders, they can all be different and the wideband itself is going to be imperfect. So keep that in mind, you see 14.9 some of those cylinders are probably 14.8 14.7 and others 15.0.


To achieve a steady idle you will need to do these things, at least
0. Make sure you have a full OEM PCV system intact, the IDLE airflow depends partly on PCV flow and may not fall within an acceptable IACV range without PCV flow. Do NOT drill throttle body.
1. Pressure test the plumbing to ensure there are no air leaks. If a cylinder leaks air its going to run higher dynamic compression and unsteady the idle.
2. Flatten the fuel map (VE table) In the areas the engine idles and returns to idle. No big jumps from one cell to the next. Best if all "4 corners" read nearly the same value.
3. Learn how the Idle Airflow PID controller works, read about PID controllers online to understand how they work in general so you can work with the integral and derivative functions respectively. Before moving on to 4
4. Tune the airflow Idle PID controller so that the IACV doesn't move at all during idle and remains near a low value like 55counts or so. It should sit at some number and kind of stay there at idle. A sign of an unsteady idle is when the IACV has to keep moving around to compensate for poor tuning, this causes surging and feedback loops worse and worse sometimes. No matter how big the cam is, you can adjust the PID so it only moves the IACV after a specific range of idle rpm.


5. Ensure the idle air fuel ratio does no bounce around. It should steady 14.8 to 15.2 at all times, fluctuating only .2 to .3 a/f at most. If the fuel map is smooth/flat but the a/f is bouncing around that is indicative of a misfire or some issue related to fuel or air. Figure out where your fuel is coming from, the VE table? Some fuel adders? What inside the ECU controls fuel for every situation? Learn to think like the ECU so you don't have to guess which map to adjust to get the desired fuel ratios.

And again make sure closed loop is disabled. You have a wideband for tuning. The narrowbands are not really good for tuning. They are for long term situational, environmental, and equipment related drift, and even then if you are the one tuning the engine with the laptop and wideband you will want to see those long-term issues and tackle them yourself immediately rather than just let the ECU compensate and cover them up for you.

If you get the airflow under control so the IACV isn't moving, and you get the idle a/f steady by flattening up the fuel map values, the idle should for the most part be steady. Then you can adjust the timing control feature to make it even more reliable.

[mjc79]

Thank you for that info i appreciate it!! I got my scanner working properly so i can log stuff and actually see it now. Made a few logs and was able to edit the ve table in the tune without stuff going nuts like before.

[Mingus]

FWI, HP tuners saves every log regardless of if you do a "Save As".

Look in your computer under: Documents>HP Tuners>VCM Scanner>Logs

They are saved with a time and date in the file name.