Strange Request for Help

Bluesman123 · December 31, 2003

This is an odd request and I'm really hoping someone can help me.

To make a long story shorter...I am trying to run a 97 5.7L Vortec in a 91 Sonoma. To make everything work, I need to get the computer reflashed with the correct fuel map, shift points, etc. but to do that they need a real VIN from a vehicle with the right RPOs AND I need the service number from the VCM that came with that vehicle (apparently they have to match up somehow).

Here's what I need:

VIN from any light duty (1500 series) 1997, 2WD, automatic, 5.7 L Vortec

This can be a C1500 Chevy or GM pickup, Suburban, Tahoe or any of the variations.

The VCM service number: The VCM is located (in most models) inside the engine compartment on the driver's side. It is black with black cooling fins clipped in a flat bracket. If you open the hood and stand next to the left front tire facing the engine you can put your hand down on it. It has 4 large connectors and a 5th little one that is on the top of mine although your's could be flipped the other way. On the top of the VCM, on either side of the small 5th connector are 2 strips of bar code. The larger/longer bar code has the SERV.NO. printed on it. This is an 8 digit number. There is a 2nd 8 digit number printed at the bottom of the same sticker...I don't know if that is important but it is so similar to the service number I would like to get that one too in case I got confused when the parts guy explained it to me.

These numbers do not need to come from a running vehicle...a junker would be fine so long as it matched the specs and still had the same VCM that it got shipped with. Its the VCM service number that has me stumped. I would just wander around a parking lot until I found the right 1997 truck and copy the VIN through the windshield, but I think they might get a little excited if I start trying to pop hoods!!

If you'd rather not post these numbers, please email me. My email address is

[email protected]

Thanks VERY MUCH and have a Happy and Safe New Year!!

Bluesman

Larry · December 31, 2003

Sounds like a cool project…

What you really need is a VCI number. Go to this website http://vci.ecomm.gm.com/vci/ and enter a VIN immediately followed by the words vci. 1GK**************vci that will give you the number that needs to be entered into a TECHII to flash the VCM.

You will have to find a VIN from a vehicle that has the same type of transmission and gear ratio as well as emissions. Looks like you already know that. You cannot use a YF6 (California Emissions) program with a FE9 (Federal Emissions) hardware or visa versa or you will be chasing ghost codes forever.

This still brings you back to your orignal request…..you still need a VIN. Maybe you can find on in a parking lot somewhere.

I help a buddy put a 1996 Vortec L31 in a 1971 K20 a while back…..lotta work!

Good luck!

Import Hater · January 1, 2004

You will have to find a VIN from a vehicle that has the same type of transmission and gear ratio as well as emissions. Looks like you already know that. You cannot use a YF6 (California Emissions) program with a FE9 (Federal Emissions) hardware or visa versa or you will be chasing ghost codes forever.

As I said in that other thread...just so long as the part number matches the powertrain you're using it for, you'll be alright. Gear ratio, tire size, and emissions certification can be changed with the flash.

Rob

99-2door · January 1, 2004

I have a 97 GMC 2wd shortwide with 5.7L & 4L60e. It has 3.42 rear gears. If you want e-mail me and I can get you the numbers off of the PCM in the morning.

BTW: A 97 doesn't have the fifth plug on the PCM. I believe only 96 has that.

Bluesman123 · January 1, 2004

Thanks 99-2DR, I'll send you an email in a few minutes. As far as the 5th plug goes, there may be more than one version of the controller for 1997. The 5th plug (C5) was only used for the ABS (I think). I'm not using it on my conversion, just have the female connector plugged in it to keep weather out.

I hope you had a great (and safe!) New Year!

Bluesman

99-2door · January 2, 2004

Sent you an e-mail

Bluesman123 · January 2, 2004

Thanks to 2DR and help from others of you on this forum and on Hotrodders.com I got the information I need. I got the VIN, VCI and service number from a truck with the right RPOs and next week we'll try reflashing the VCM.

I really appreciate the help for all of you who posted and emailed good advice.

Bluesman