HOW TO 99-02 PCM into 97-98 Corvette WITH PICS!
 

Hello!

There seems to be alot of misinformation about the computers in our cars, how they work and if they are interchangeable or not.

First off let me start with what type of knowledge i have, and what tools are avaliable to me so you can judge wither or not you would want to tackle something like this yourself. I am an Aviation Electronics Tech for the last 9 years in the Navy, so i do have electrical knowledge and background, that beeing said cars are very different from Helicopters, so in reality i didnt put much of it to use other then basic electrical theory. Know, one key to figuring this out on my own is my best friend is a well known Tuner in the North East Florida area, so we i have full access to EFI Live tuning suite and his knowledge and help, without him i could not have done this (would not even have attempted it).

Now lets get started! The first thing i did was pay a visit to my local Chevrolet dealer to make photocopies of the pinouts from a 1997 Corvette and a 2000 Corvette, i knew i could get this from the net but i wanted to be 100% sure i had accurate info. Of course i also purchased a used 99-02 LS PCM, mine came from a Trans am but you can get a PCM from any LS vehicle of those years, Corvettes F-Bodys and Trucks/Vans, they are all the same. The trick is to check the color's that are marked on the PCM's connectors, if it is Red/Blue, then the PCM will work. Also you will need to buy the 2 brackets that hold the PCM into the car, the older PCM is a different shape so your original ones will not work, just order both the brackets from a dealer for a 2000 COrvette, there 12 dollars apiece.

Well then, time to work! Obviosly youll need to disconnect the battery and jack up the front of the car. Remove the passenger front wheel and the splashguards behind the wheel and Viola your staring at your PCM! The first pick here is what youll see, i have already removed the PCM and the brackets and pulled back the shielding from the wire looms.

http://i182.photobucket.com/albums/x...1/DSC00909.jpg

This is where the fun begins, and it REALLY helps to have a partner with a label maker for this step. Plan for this to take the better part of an afternoon, this is not something you want to rush. Basically, you take apart the PCM connectors and 1 by 1 remove each pin, Labeling as you go. What i did was i looked up the pin on the 97 PCM Pinout schematic i had, read what the signal was, found that signal on the 2000 PCM Schematic and labeled the wire to where it would need to go back into the connector for the new PCM. YOU DO NOT HAVE TO CUT ANY WIRES, all you are doing is removing the wire from connector, using your pinout diagrams to figure out where it would be in the connector for the new PCM and after they are all labeld reinserting them into the connectors in new locations. Here is a pic of what youll be looking at after labeling

http://i182.photobucket.com/albums/x...1/DSC00913.jpg

Now, once they are all removed and labeled with there new locations, all you do is start reinserting them into the connectors in there new homes!

http://i182.photobucket.com/albums/x...1/DSC00914.jpg

Once you have them all re-installed ou can go ahead a wrap them back up to make them nice and neat and weatherproof

http://i182.photobucket.com/albums/x...1/DSC00922.jpg

http://i182.photobucket.com/albums/x...1/DSC00920.jpg

after your done wrapping, you can put the connector backshells back together and install your new PCM brackets into the car

http://i182.photobucket.com/albums/x...1/DSC00923.jpg

then, install the new PCM and connect everything back up and VIOLA you are done!

http://i182.photobucket.com/albums/x...1/DSC00928.jpg

Easy right? well yes it isnt that difficult, i cant stress enough taking your time if you try this yourself when you are removing and labeling the wires, that is the most critical step.

lastly, there is some programming involved in this. Obviously the new PCM will need to be flashed with your Vin, and you will pop fuel tank pressure sensor codes when you activate the newer Corvette operating system in the PCM, this is due to the 97-98 Corvettes do not have the tank pressure sensors installed, so simply program out those codes and you are good to go.

So, now you have a 99-02 PCM in your 97-98 Corvette! Youve opened a whole new world of tuning oppurtunitys for your car, expanded VE tables, Custom operating systems from EFI LIve and you can real time tune with tools like a Moates Roadrunner!

interesting........

that was my first thought when doing this was first proposed to me lol

You simply can not flash a 98 VIN into a 99+ PCM. The two PCMs have complete different table structure and layouts. LS1Edit and HPTuners will not work correctly as they will read the VIN and try to writes tables for a 98 into a 99+ PCM. That is a good way to ruin a PCM.

Keith

IIR there is issue with fuel sender/cluster gauge. Did you ?

Some links on doing conversion:
http://forum.efilive.com/showthread.php?t=4964
http://forum.efilive.com/showthread.php?t=5066
http://gmtuning.info/wiki/index.php/98PCM

:eek: :willy:
Thanks for the information. I might hold off on this one for a while.
Where are you located? Do you make house calls? :rofl: :lol:

I would rather stick with Edit than go through all that.

Great work!!:thumbs:

BC

hehe anything can be arranged :thumbs:
Jacksonville FL

Just for clarification, you can use a RR on a 98 without doing the conversion.

yes and no, he does make a roadrunner that fits the 97-98 car, but it is an entire different PCM you have to buy that is limited to only those 2 years, so not many of them out there

Correct. Just saying that there is alternative to doing the wiring conversion for the 98 folks and still have the real time tuning features. It's still based upon the old bastid child 98 PCM though.

:iagree: I got a rash looking at it being done:willy:

By the way do you work on the SH60?

Bill

sure do, SH-60B :)

I just retired from Lockheed where the B model avionics system was developed/installed. I used to be the Program Manager for the CASS Development Team that was developing CASS I level tests for avionics units on the MH60-S and MH60-R models.

I spent a lot of time in the Jacksonville/Mayport area over the last decade.

Bill

eurospec1 -- you have my sincerest and utmost respect for tackling something new, and doing a damn fine job at that.

:cheers:

PS -- the latest EFILive is awesome, isn't it? I have an old V1 cable with the commercial license so I can do OS-rewrites (working on a speed density tune right now) but will be upgrading to V2 soon.

Thank you, and yes the New V2 EFI Live is amazing

Awesome, i love the platform its been real good to me over the years

It was good to me also. Spent the last 10 years of my career working on it and had a ball. The Navy people (both civilian and military) I worked with were great.

Bill