Eprom burning for the 8746 ecm (89-92 TBI L03 f-body's NOT 88 see note below)

This page is for all you guys with the TBI efi system and have the 8746 ecm. I'm not going to even dip into the 7747 ecm. All I'm going to say is that lots of guys have switched to ecm because it's so popular and so it's been hacked very well. The 8746 has been hacked recently so there is no reason to switch over. There are lots of options for hardware but I'm going to list exactly what I have.
Note: The 88 TBI ecm can be swapped for a 8746 or 7747. It's completely plug and play, not wires to cut.

Just some side notes so you know if you have the 8746 and if you need backups of your eproms here are some bin files. If you have any of the following bin files please e-mail them to me. I'd like to gather then for future reference.

RPO codes: Options & Emissions Designation and description Production Broadcast Code(s)
MD8 A/tranny (th700r4 or 4L60) (2.73 rear gears)

ANTS AXKS

NB2 California emissions
MD8 A/tranny (th700r4 or 4L60) (2.73 rear gears)

ANTT AXKT

NA5 Fed emissions (other 49 states)
M39 M/tranny (3.08 rear gears)

ANTP APTX AXKU

NB2 California emissions
M39 M/tranny (3.08 rear gears)

ANTR APTY AXKW

NA5 Fed emissions (other 49 states)
  89 Caprice police car with Lo5 350 ANLU
  89 Caprice LS Bourgham Lo5/350ci, 200r4 auto tranny
(2.73 rear gears) - Fed emissions

89 Caprice LS Bourgham Lo3/305ci, 200r4 auto tranny
(2.73 rear gears) - Fed emissions

AUML


APFN

You will need:

What: Source:
Pocket Programmer Xtronics $130
DataRase II EPROM eraser DigiKey $40
Eproms YOU DON'T NEED A MEM CAL
You can get "pulled" eproms for like $2.00, ask on the www.thirdgen.org message board.
JDR look for 2732A-2F1 $5.90 each
Tuner Cat Tuner program Tuner Cat $70
GM $61 ECM Definition (.tdf) file Tuner Cat $20

Total:

~$300

Now first thing you're going to want to do is make a backup of your stock chip and send it to me so I can keep it on file :-)

If you don't know where the ecm is don't even bother programming your own chip. You need to spend MORE time on www.thirdgen.org.

Take off the backdoor on the ecm (2 hex screws) and you'll see the chip. I just used a small screwdriver to pull it out. I pried on each end of the plastic piece until it was loose enough for me to just pull out. Now comes the harder part and don't blame me if you screw it up. What I did might not be the perfect way but it worked so it is a way.
You'll notice that the plastic piece is holding the eprom in by the prongs.
Just push on the sides of the plastic and that'll bend the prongs inward. Then pull away the plastic sides and one side of the eprom should pop up.
My friend Pablo says that after a while the plastic piece gets easier and eventually you can just push from behind and pop the chip out. That probably works too but just be careful not to break any of the prongs off!
Once you have the chip out you can go on to the next steps.

1.) Plug in pocket programmer into back of computer.
2.) Plug in the power cord for the pocket programmer.
3.) Run the software: fileprom.exe

 

4.) Type in 27 then enter. 27 is for the 2732a eprom which programs at 21volts. If you have some other eprom like a 2732 with no number, then choose the accordingly.

5.) Place the eprom in (look at the diagram on the side to figure how the chip goes in) the zif socket. For our chips there should be 4 empty rows above and make sure the key/notch of the chip is in the correct way!

6.) This is your menu, study it, know it, love it, hate it!:

7.) We said we were going to backup your current chip so either type in 4 and then enter or just press "m" on the keyboard as a shortcut.

8.) It's going to ask for a directory path. I recommend keeping it short like c:\eprom . Don't type in a file name for it yet. Next screen will ask for they file name and it's a good rule of thumb to enter in description as the name. For example, my car is a 91 tbi l03 auto so I would name it 91camarol03tbiauto.bin. Don't forget about the .bin as the file extension.

9.) It should take less than a second to read the eprom and write it to the file.

10.) Press V to verify. That's it, you've now got a backup so it's time to have fun.

Now I hope you have some extra eproms to work with, saves you some time.

Open up Tuner Cat software and make sure you have the definition (.tdf) file in the Tuner Cat's installed directory! In the program go to the pull down menu "ECM" and select "ECM_61", if it's not there then you've installed the .tdf file into the wrong directory.

Okay, the best way to start is to read up on ALL the eprom burning and programming. The following is a list of resources and places to ask questions. You'll need to learn a lot before you go about changing a lot.

By now you should have a good idea of how to program your own chips so I'm not going to bother telling you the little stuff. Just look at the menu and it's pretty straight forward.