HOW TO: Setting up MAF Fuel Trim Graph in VCM Scanner V3

[schpenxel]

Voltage offset would be covered in the setting up a wideband how to if I'm understanding what you are asking.

You'd change the second part of the formula to adjust for whatever delta you're seeing

http://www.hptuners.com/forum/showth...l=1#post416605

Instead of 0.72 you might have 0.74 or 0.68 to account for a voltage offset in picture below



Or if I am misunderstanding then give more detail and I'll try to help.

[gottogo]

That's what I was looking for. Thank you.

[Hib Halverson]

The "Tuning School" covers a similar procedure in their Basic Course.

One difference is that they advocate LTFT only whereas you advocate STFT+LTFT.

What's the advantage of doing it your way?

Also, when you bring STFT into the picture, don't you also introduce a potential error due to the intentional fluctuation of STFT which the ECM does to improve catalytic converter function?.

[schpenxel]

It's a small percentage, but yes.. though as long as you get enough hits then it averages out and doesn't really matter

The problem I have with using LTFT's is they don't represent all the error/fuel correction. You could need a 5% adjustment in one spot and 10% in another. LTFT's may be 5% for both of them.. then STFT's maybe an extra 5% on the second spot. If both of those places are represented by the same fuel trim cell then they'll have the same long term fuel trim value more than likely.. so you end up not fixing both if you only use LTFT values.

It's easier for me to just combine them (or turn off LTFT's altogether and just use STFT's).

Either way will work.. just my preference. I just like having the entire fuel correction taken into account.. I don't see any reason not to personally.

[Jeep LS]

Very helpfull tread. Thanks! Now i've been struggling with step 11. I paste the column axis label from my tune but once i close the graph text window the frequency column axis are not there anymore... I've tried to scan the date and it's actually loging information but there's only only cell appearing in the graph. I know i must be doing something wrong but i've been trying to find the problem by myself for the last week every minute i had... You help is welcome! Please find attached pict. of step by step of my files.

Graph after paste.PNGGraph when reopened.PNG

[Jeep LS]

Please find attached my latest tune and latest scan.

Thanks,

Attachment 60262


Attachment 60261

[schpenxel]

Very helpfull tread. Thanks! Now i've been struggling with step 11. I paste the column axis label from my tune but once i close the graph text window the frequency column axis are not there anymore... I've tried to scan the date and it's actually loging information but there's only only cell appearing in the graph. I know i must be doing something wrong but i've been trying to find the problem by myself for the last week every minute i had... You help is welcome! Please find attached pict. of step by step of my files.

Graph after paste.PNGGraph when reopened.PNG

It's not copying/pasting correctly.. it's putting spaces between the 1 and 9 in 1900 for example which I think is the root of the problem. I'll try it using your tune/config in a minute

What version are you on?

[Jeep LS]

It's not copying/pasting correctly.. it's putting spaces between the 1 and 9 in 1900 for example which I think is the root of the problem. I'll try it using your tune/config in a minute

What version are you on?

i use version 3.0.

thanks,

[schpenxel]

Does Canada switch . and , in numbers like they do in Europe (vs. the US)?

[Jeep LS]

The files use , and not . Was it the answer you were looking for? i've attached a screen shot taken of the Scanner

Data , vs ..PNG

[Jeep LS]

You might just of found it!

I've tried to erase all the spacing in between the number like: 1500 1650 1800 instead of 1 500 1 650 1 800 and the numbers are now staying in the file when i close it down. I will try to get a scan done now and see if i can get numbers (%) transfer to my Tune file for LTFT.

Hopefully this is it!

[schpenxel]

I'm pretty certain that's it.. I'm just not sure why it isn't pasting correctly. I suspect maybe something different with your language settings since you are in CA?

But if you go through and fix spaces then it should work

[Jeep LS]

You found it! Man i can't believe you found it in 15 minutes only!
I was able to perform 3 LTFT scan and have it transfer into my tune. The LTFT is now around +/-5%.
Now i had to close my computer and i can't get the scan data to paste into the tune anymore.
I wonder if it could be the . vs , like you mentioned earlier. If you look at the pic attached you will find
that the data in channels use , and the data in the graph use dot. The data in the tune use , as well.
When i try to copy/paste the software doesn't allow me to do it but i can edit the numbers one by one.

I've search for ways to change the data , vs . and can't find tread on that subject.

thanks,

[Jeep LS]

Here's the pic of my scanner.

, vs . question.PNG

[schpenxel]

The graph looks OK to me... are you pasting it into the MAF table in the tune in VCM Editor?

[Jeep LS]

The graph looks OK to me... are you pasting it into the MAF table in the tune in VCM Editor?

For some reason the data coming out of the graph in the scanner are using . and they wont paste into the Editor. So i've had the decimal turned to 0 and works just fin now.
So know, i was able to make 8 scan run and had it past into the tune using mostly half % which seems to be more accurate now that i can't use decimal.
Here's a picture of where i'm at now.
i believe i will have to tune the high frequency now that i've had the low frequency increase so much.
Thanks for your help and support.

MAF LTFT SCAN AFTER TUNE 19.PNG

[schpenxel]

Must be an issue with the language differences or something

[mowton]

This happens when International customers are not running their PC's in US standard...which is understandable and things like the period are not recognized as a decimal point. Gets some getting used to, as well as reading and navigating around Windows in German, Norwegian Swedish etc :-)

Ed M

[orripid]

Awesome write up

[02Ls1]

Hi guys, I'm new to this and I was wondering with this table I can tune a car using LTFT if they come up with different injectors, cam, heads etc..?

Would I need to set up the file in MAF open loop?