View Full Version : PCM info for NorthStar

02-01-06, 01:24 PM
I am trying to do some digging on the NorthStar PCM, wondering if you N* owners can help.

1. Who is the PCM supplier? I know it isn't Motorola, I suspect Delphi, as they are main GM supplier.
2. What bus protocols for the 96-99 and the 2000-up? CAN, Class II (SAE J1850), ?
3. Does anyone have any pictures of the inside with some IC's that can be identified?

Thanks! I won't ask if I had a NorthStar car handy, but I don't.... Yet....


02-01-06, 01:39 PM
hmmm...what are you planning to do??

02-01-06, 01:59 PM
It's cracking time....

I am determined to figure out at least WHY no one has been able to do it. And my goal is to succeed.

We are working with standards, so I am puzzled why, is it just lack of effort or like Dodge did on the Hemi, encoded the output where it was harder to crack. But that defies the EPA ODBII standards.

02-01-06, 02:57 PM
Cool! Glad somebodys determined to crack the codes!

02-01-06, 03:03 PM
I talked to one guy who has cracked some LS1 stuff and said a new PCM takes around 3 months to crack. Maybe if we can get more heads together on the same goal, we can do it sooner.

As we say at work, keep throwing bodies at it till it gets done....

02-02-06, 10:06 PM
check with the guys at auto tap and see what they have
Website claims to have a programmer for all GM OBD2 v-8s.
Also some time back I inquired at SuperChips,whose right up the road from me,and they said they could custom program my 96 Aurora.
I like the HP tuners that you can DIY.

02-04-06, 03:10 AM
Will do, odd, by the response on this thread, I can see why no one has messed with breaking the code, seems like there is very little interest. Or am I just reading this wrong?

02-04-06, 08:16 AM
I lost some of the interest when I switched from a Northstar to an LT1. The thing I think it might be, is not too many people know how to crack car computers. So they can offer little advice, and are tring not to clutter up a thread. As for getting a computer, I'd hit a junkyard, and save some $$.

02-10-06, 10:39 PM
Well is it delphi? And whats the part number?
I dont think it delphi since I could only find part that are for delphi:
Alternator Camshaft Sensor SS10003
Coolant Temperature Sensor
Crankshaft Sensor
DIS Coil
DIS Module
EGR Valve
Electric Fuel Pump FE0073 Stamped EPT Or EPW On Sender
Evaporator EP20003
Fuel Injector FJ10054
Fuel Strainer FS0030
Heater Core HC0172
Knock Sensor AS10007
MAP Sensor PS10058
Modular Fuel Pump FG0010 Stamped EPV On Sender
Oxygen Sensor ES10049 2 Required
Radiator RA1208 -
Throttle Position Sensor SS10429
Wire Set

02-11-06, 09:54 AM
Will do, odd, by the response on this thread, I can see why no one has messed with breaking the code, seems like there is very little interest. Or am I just reading this wrong?

I'd try and find this stuff out but mine's a 95, don't have a 96+ handy either.

02-11-06, 10:50 AM
You are't going to get much help from AutoTap. Their latest adapter and Beta software will let me access nine generic parameters in my '04 CTS. They are way behind the curve with CAN enabled stuff.

02-11-06, 02:16 PM
It's cracking time....

I am determined to figure out at least WHY no one has been able to do it. And my goal is to succeed.

Because it's work. Unpaid charity work at that.

On top of that, you have to have a solid foundation in assembly, and electronics (to decode the ALDL stream, translate that into memory locations, and go backwards)... Having a schematic obviously would be a big help (there are none).

To be frank, it's a big PITA with little to gain. Say you did crack it, what do you gain? Maybe a few extra horses when you can modify the spark tables a bit? Change the rev limiter? MPH cutoff? What's the ultimate goal?

02-11-06, 04:14 PM
After seeing the amount of parameters in the LS1 code, what you can do is amazing. I guess for me, I like to mess around. And cars like Mark's, it might be a Godsend too. You can likely make the PCM use a 2 bar MAP, where now it is only a 1 bar. So the PCM can manage all the boost calculations (timing/fuel) etc.

02-11-06, 05:37 PM
Like I mentioned previously in another thread, I am close to releasing a plug and play tuneable GM computer for the northstar. Boost will be a possibility. Custom tuning for cams, etc will be done with ease. It won't have all the features the stock OBDII computer will have, as it is OBDI, and it certainly won't talk to any of the other computers, but it will be a major step forward in tuneable, affordable northstar computers.

That being said, I doubt anyone here would be interested in such a thing, it's mainly aimed at people with northstars in other cars (dune buggies, fieros, hotrods, etc).. i.e. people who don't care about all those other computer systems. But plug and play for about $500, with wiring harness is tough to beat. On top of that it's a GM computer with more features than anything Holley, etc can give.

With respect to the OBDII northstar computer hacking, turning it into a computer capable of boost would be quite a feat. You would have to reprogram actual code segments. Hacking the computer is one thing, a very labor intensive (brain melting) thing, but actually rewriting code would be...well... painful. I'm not trying to stop anyone from attempting by any means, but I just see people asking "why isn't it hacked yet?" as if it's some walk in the park... It's not.

F4A7 LF4A7:ldaa #0x40
jsr LF0C9
ldx #0xF8E2
brset *L002A,#0x40,LF4BC
brclr *L0004,#0x01,LF4BC
ldx #0xF8F3
bra LF4C2

LF4BC:adda #0x0A
ldaa #0xFF ;LOAD 255
staa *L00E8
brset *L002A,#0x40,LF4D3
cmpa #0x78
bhi LF4D8
cmpa #0x6A
bhi LF4DB
LF4D3:bclr *L0004,#0x01

^^ That's a sample of what I'm working with right now. If you can't read that in "english" terms, you have a lot of catching up to do. I have a very limited assembly knowledge. It's barely enough to get what I'm trying to do done. Hacking an ECM is beyond my reach...

02-13-06, 02:17 AM
I say go for it. Let me know if there is anyting I can do to help, short of testing totally experimental software on my car.

02-13-06, 12:10 PM
hey my 97 ETC is fully covered by the dealer for the next year if you wanna try some software out on mine for more power im game then if it fu*ks it up ill replace all the stock stuff if its still screwie ill take it and make the dealer fix it lol