GM V6 OBD2 PCM

[antus]

Have a look at the faq to get started. Link near top right of the screen. Look at the1s enhanced code.

[ejs262]

blast from the past... Turbo_V6 on youtube (I'm sure he's on here) made a video about PCM hacking, and I have a car that I can try and mess around and find out with, so I'm going to slowly start trying to take another crack at this.

Turbo_V6 Video

https://www.youtube.com/watch?v=iU_yiOW ... l=Turbo_V6

at this point, I'd like to try and see what I can make happen with some of the tools at my disposal, without too much more investment. Right now, I have DHP Powertuner, Tiny Tuner and the associated software that I can use to establish existing tables in Ghidra, and build off of work that's already been done for me.

the car that will be getting the attention is my 2003 Pontiac Grand Am that I call "Gran Damn" it has a 3400 V6 with later model heads and intakes, a custom exhaust, a cam, a five speed swap, and a few other oddities, I'd like to explore what I can make happen with the stock PCM, and maybe develop some improvements.

https://www.youtube.com/shorts/_yZuIJQwcJQ

[antus]

If you build the current development branch of pcmhammer it should be able to read your p04, but very slowly. If it doesnt recognise the OSID then you'll need to look at adding more P04 IDs and chip sizes to pcminfo.cs. Then you'll need to try and figure out why the supplied kernel in kernel/p04 is having trouble. Note that it could be just bad luck with the bin I was reading due to a particular sequence of bytes in the bin. There is another thread about it on the forums. Others were not able to reproduce it. This might mean that its worth continuing and revisiting that problem later. The more recent thread is here: viewtopic.php?f=4&t=8008

[ejs262]

If you build the current development branch of pcmhammer it should be able to read your p04, but very slowly. If it doesnt recognise the OSID then you'll need to look at adding more P04 IDs and chip sizes to pcminfo.cs. Then you'll need to try and figure out why the supplied kernel in kernel/p04 is having trouble. Note that it could be just bad luck with the bin I was reading due to a particular sequence of bytes in the bin. There is another thread about it on the forums. Others were not able to reproduce it. This might mean that its worth continuing and revisiting that problem later. The more recent thread is here: viewtopic.php?f=4&t=8008

So, I currently have read/write capability with an AVT 852 and my DHP powertuner, and winflash. I'm going to be very blunt about the fact that I have no idea what I'm doing, I'm slowly trying to learn, and would be more than happy to share whatever results I come up with.

if anyone has a good crash course for me to read/follow that takes me further than what Turbo_V6's video does, I would greatly appreciate it.

[ejs262]

longshot, but has anyone here seen this with a DHP powrtuner?



the interface will read the PCM, but not read DTC's, or datalog anymore for some reason. I'm using an AVT 852 cable.

[MudDuck514]

blast from the past... Turbo_V6 on youtube (I'm sure he's on here) made a video about PCM hacking, and I have a car that I can try and mess around and find out with, so I'm going to slowly start trying to take another crack at this.

Turbo_V6 Video

https://www.youtube.com/watch?v=iU_yiOW ... l=Turbo_V6

snip

You need to be aware that the 4.3l v6 he is working with uses the P01 PCM and not the P04 the you have.

Mike

[ejs262]

blast from the past... Turbo_V6 on youtube (I'm sure he's on here) made a video about PCM hacking, and I have a car that I can try and mess around and find out with, so I'm going to slowly start trying to take another crack at this.

Turbo_V6 Video

https://www.youtube.com/watch?v=iU_yiOW ... l=Turbo_V6

snip

You need to be aware that the 4.3l v6 he is working with uses the P01 PCM and not the P04 the you have.

Mike

Very much aware, but the principles still apply to some degree. both use a Motorola 68K processor. That said, I haven't gotten very far yet. I have the code in Ghidra, and begun looking for things, I see some things very similar to what he shows in his video, and some things that aren't. Prime example is the MAP PID doesn't appear to be coded the same in the P04 as the P01, I suspect this is because the P04 was used in boosted applications from the factory, and could be equipped with 1 bar, or 2 bar map sensors, whereas the P01 was only equipped with 1 bar as far as I am aware.

[bubba2533]

Is there a popular OS that would be good to disassemble? I can take a look at it and see what I can find.

[ejs262]

I've been able to disassemble the bin file with Ghidra, and verify that the code disassembled at least partially correct based on the work of Eddie Blattner (if you're on here, thanks!) He developed a tuning suite for the P04 PCM's called Tiny Tuner, along with a "Thingy" program that was used to find the tables and parameters in the bin file. I've been able to use the tools he developed to go to addresses in the disassembly and see values that match the values in the bin. I'll call that a win.

Tiny Tuner:

TinyTuner_111810.rar

(189.82 KiB) Downloaded 63 times

The associated database file that has most of the tune parameters

Active_TTDB_09-20-13.rar

(392.44 KiB) Downloaded 58 times

The database editor "Thingy"

TheThingySuit_PublicRelease.rar

(316.2 KiB) Downloaded 62 times

My biggest problem, is that I don't speak the language yet, or any code language outside of some of the language used in Allen Bradley PLC logic(and even that isn't extensive).

Back when I first embarked on this journey, the go-to OS for a performance tune on a P04 PCM was the 1223462 OS, for a 2002 Pontiac Grand Prix GTP with an L67 Supercharged 3800, and 4T65hd automatic, I'd guess it's still the preferred file, but I'm really not sure, I've been out of the OBD2 V6 Scene for a while, the car I started all of this on now has a MS3 Pro, the only reason i'm really back to it, is that I have a 2003 grand am, with a 3400 that I'd like to play with a bit. I attached a copy of the 12223462 bin if you'd like to take a look, as well as the 03 Grand am Bin that I have made changes to for my car.

'02Grand Prix GTP L67 os12223462.bin

(512 KiB) Downloaded 61 times

Gran Damn 12583339.bin

(512 KiB) Downloaded 53 times

For curious parties, the Gran Damn is a 3400 with a 5 speed, a big cam, and a few other goodies, it's stoopid, but kinda fun for what it is.

https://youtube.com/shorts/_yZuIJQwcJQ?feature=share

http://www.realfierotech.com/viewtopic. ... dd7c910b22

I'm kinda dumb like this...

[In-Tech]

Maybe this will help, I don't know the addresses without a shit ton of work but maybe this will help you identify stuff. This is from TunerCat software.

I don't have this 2003 car anymore but it might help with your 2003 3400

2003_3100_GrandPrix.txt

(167.45 KiB) Downloaded 50 times

'02Grand Prix GTP L67 os12223462.txt

(167.4 KiB) Downloaded 55 times

Gran Damn 12583339.txt

(165.64 KiB) Downloaded 49 times