Hello all, I'm new to this forum but not to PCM/ECM tuning/programming. I've done lots of it on TPI ECMs (MAF and SD) in the past but I just purchased a 96 Z28 and could use a little help with it.....

The car has had the A4 to M6 swap partially done to it. The swap is mechanically complete but the PCM has not been touched. I have a constant SES light right now. The bright side is that I got LT1 Edit with it - just the one-user version I am told so it is locked to my car's VIN (at least that is what I understand is the way it works with LT1 Edit).

So my question is regarding the necessary changes for the swap to the T56 setup from the 4L60E one that was in the car. I loaded LT Edit onto my computer and got the file off the car and started looking around and reading various things but I did not see any type of flag or table for changing the transmission type that the file has loaded in it.... Do I need an entire new file that is designated as an M6 for the car and then do any other changes I want from there? It seems as though the transmission type is "behind the scenes" in the code and cannot be changed. The car also has 17" wheels on it and the PCM file still has the stock size loaded in it and I will be swapping the 2.73 gears out for 3.73s soon so I am wondering how this operation is accomplished with an OBDII PCM like the one in my Z28....

If this was a TPI you simply change the trans flag and drop all of the transmission data for the auto to 0 and you are done . I would really like to gain all of the functionality of the vehicle (well, aside from CAGS) in regards to the T56 as well so any tips are welcome.

Thanks in advance,
Matt

 

May be you need the reverse lock out ( lockout when the car

is moving forwared)

 

Well I did get Autotap with the car as well so I will have to get my laptop on there and see what the DTC is that is flagging the SES light and go from there... I suppose not having the reverse lockout solenoid wired to the PCM would set some sort of DTC....

 

Can't you get a stock M6 .lt1 file from someone on the lt1 board?

I only have TC but in there here are the differences (that are obvious).

Turn off for M6:
1. C.A.R.S (reverse lock out I believe. Of course you would actually turn this on if you had the soleniod).
2. Brake Switch Shorted
3. Brake Switch Open Diag 38
4. Trans Temp High Diag 58
5. Trans Temp Low Diag 59
6. No Vss Signal Diagnostic, Error 72
7. Force Motor Current Diam. Error 73
8. Traction Control Diag Error 74
9. Trans System Voltage Diag, Error 75
10. Trans Fluid Temp. High Diag, Error 79
11. Trans Shift "B' Diag, Error 81
12. TCC Stuck on Diagnostic, Error 85
13. TCC Enable Error Diagnostic, Error 90

Turn ON for M6:
1. Shift Light Diagnostic, Error 91

Hal

 

I dunno... This whole "locked to VIN" thing is pretty foreign to me. Can I just take an M6 .lt1 file and flash my car with it and it's a done deal? I guess that is basically what I am asking.... But I would change the enable for the CAGs to like 255 mph or so .

I use TunerCat for my TPI stuff so I know how that works quite well. It has flags for setting things like the transmission type and also ones for turning some functions completely off (VATS for instance), but I don't see any of that sort of thing in LT1 Edit.....

EDIT: Hey wait a minute.... I wonder if I would be better off just buying the .tdf definition file for this LT1.... Hmmmmmm

EDIT2: Nevermind..... no .tdf for any OBDII stuff..... No using Datamaster either.... This is going to be fun .

 

Yes. "Vin locked" is really more like "pcm locked". The pcm contains the vin# which can not be altered but it may not match the actual vin of the car. Lt1 edit won't let you program more than one pcm but you can use any .lt1 file to do it.

 

Really.... so if the VIN listed in the little block of notes in LT1 Edit for the specific .lt1 file I am using is a different VIN than the one that the original flash in the PCM had it will still let me program the PCM with either (or any for that matter) .lt1 file and the car is none the wiser?

 

The real vin of the pcm can not be changed so a flash will ignore the vin listed in the program file. To see the change, flash the new program into the pcm. Then, read it back out and the change will show up (I think you need to start the car between the write/read or else the car won't start (just disconnect battery for a few minutes if this happens).

Hal

 

Ahh... Makes sense. So what is it that LT1 Edit is locked to? Does it check the VIN of the PCM before you read/write and only allow communications with that one VIN you pay for?

THANKS!