LTFT values

[beerman]

This is from my 1997 Camaro Z28 I don't know if it applies to other GM models

Using my Atap I logged some data and once I was done I sent the following requests in "LDV" mode.
I then compared the results to my Atap log.
J-2190 MODE $22 ENHANCED PID REQUESTS $FC1F-$FC28 (ALL VALUES ARE IN HEX)
01 01 41 07 6C 10 F1 22 FC 1F 01 F5
01 01 41 07 6C 10 F1 22 FC 20 01 F6
01 01 41 07 6C 10 F1 22 FC 21 01 F7
01 01 41 07 6C 10 F1 22 FC 22 01 F8
01 01 41 07 6C 10 F1 22 FC 23 01 F9
01 01 41 07 6C 10 F1 22 FC 24 01 FA
01 01 41 07 6C 10 F1 22 FC 25 01 FB
01 01 41 07 6C 10 F1 22 FC 26 01 FC
01 01 41 07 6C 10 F1 22 FC 27 01 FD
01 01 41 07 6C 10 F1 22 FC 28 01 FE


MODE $22 ENHANCED PID RESPONSES $FC1F-$FC28

01 01 C1 0A 6C F1 10 62 FC 1F 80 84 84 81 C0
01 01 C1 0A 6C F1 10 62 FC 20 88 82 7F 7F C0
01 01 C1 0A 6C F1 10 62 FC 21 80 80 81 84 BE
01 01 C1 0A 6C F1 10 62 FC 22 80 80 87 8A CB
01 01 C1 09 6C F1 10 62 FC 23 82 80 80 3C
01 01 C1 0A 6C F1 10 62 FC 24 80 85 87 85 CD
01 01 C1 0A 6C F1 10 62 FC 25 84 86 7D 7F C3
01 01 C1 0A 6C F1 10 62 FC 26 80 80 81 81 C0
01 01 C1 0A 6C F1 10 62 FC 27 80 80 82 85 C6
01 01 C1 09 6C F1 10 62 FC 28 87 80 80 46


And what is all this mean you say
looking at my logged Atap values
I converted my LTFT values to HEX and I wound up with


LTFT1 FTC LTFT2
84 1 85
84 2 87
81 3 85
86 4 80
82 5 87
7F 6 7D
7F 7 7F
* 8 *
80 9 80
81 10 81
84 11 81
* 12 *
80 13 80
87 14 82
80 15 80
82 16 87
* NO LINES OF DATA LOGGED

Then I put it all together ;D
LTFT1
FTC CELL ? 1 2 3
HEX VALUE 80 84 84 81

FTC CELL 4 5 6 7
HEX VALUE 88 82 7F 7F

FTC CELL 8 9 10 11
HEX VALUE 80 80 81 84

FTC CELL 12 13 14 15?
HEX VALUE 80 80 87 8A

FTC CELL 16 ? ?
HEX VALUE 82 80 80

LTFT2
FTC CELL ? 1 2 3
HEX VALUE 80 85 87 85

FTC CELL 4 5 6 7
HEX VALUE 84 86 7D 7F

FTC CELL 8 9 10 11
HEX VALUE 80 80 81 81

FTC CELL 12 13 14 15?
HEX VALUE 80 80 82 85

FTC CELL 16 ? ?
HEX VALUE 87 80 80

The values may be off a little due to the Atap logging a LTFT value then switching the FTC. I see this alot when I go to WOT. I could log smaller amounts of parameters to correct this.
My FTC 15 figures are off because I am using an OBDII Flash file with a BLM LOCK patch (from Carputing)

My LTFTs are off a little (B1 vs. B2) because I had a new O2B1S2 installed under warranty last fall.

I got the PID list from Tom Hussey's post in the GM ECM Archive.

The unlabeled $80 are probably FTC 17 18 AND DECEL


PIDS $FCXX must be stored or learned values (NVRAM?)
I noticed went I send MODE $3C $08 I get the original GM calibration ID (Stored in area with VIN)
If I send MODE $22 $FC $02 I get the current GM calibration ID ( Reflashed Cal ID number)
But that does not get reset when the PCM is reset?

more on that later

[Keith@HPTuners]

Hmm.. interesting info although I am uncertain what you're getting at.. ??

How are you sending/reciving data using the autotap cable?

[beerman]

I use com port toolkit http://www.compt.ru/,or docklight http://www.docklight.de/ to send hex commands to my autotap hardware. The information thats in the LDV document http://www.vehicleinterface.com/asse...xxP1-1103m.pdf
I sent j-2190 mode $22 (PIDS) messages
and I found were my fuel corrections are stored so now I can tune my car's MAF based on my fuel correction

[Keith@HPTuners]

I'll have to check out the tool kit.

Standard autotap won't monitor that for you? or are you just trying to accomplish it by hand?

Looks to me like your using the V2 cable correct?

[beerman]

Yes, I use Atap AT123 V2 with the enhanced regristration so when I use Atap's software I can see whatever PIDS they decided to define or the defined PIDS my PCM supports.

As for the standard atap (generic) I believe its only J1979.

I think that if I had Pauls EFILive all I would need is to buy the regristration code for it to work.


Comport toolkit is kind of neat because you can log and write macros. I bought the reg for that program only $29.00. If I wasn't a total programming NOOB I would do something of my own. I thought about doing something in Excel that would send HEX commands to COM1 but thats still out of my league right now.

[Keith@HPTuners]

Perhaps I will start an open source MS VC++ project.. something on my mind.