ADM

I have purchased a 1997 LT1 car and I have looked around for tuning software for LT1 OBD II computers and it isn't really cheap + I will need a new cable.

Already laying around is my 1994 PCM with a tune for exactly the same mods that I am installing onto this 1997 car. And not to mention I have a full version of Tunercats with the definition file already installed on my Windows laptop + an ALDL cable.

So, is it possible to convert the car into OBD I? Has anyone done it before?

What is needed to do the conversion?

stevo9389

from what I remember you just plug the PCM in and change the knock sensor

ADM

What about the OBD port?

Are the pigtails different for the 94 knock sensors?

stevo9389

we traced the data line and wired in a obd1 connector to the glovebox. sorry I don't remember the color of the wire (wanna say purple) but I am sure we found it off of some stuff from shbox's website

I am fairly certain the pigtail connectors are the same

ADM

Thanks for the help buddy.

Just one last thing. Isn't the internal electrical circuit for the 97 transmissions different than the 94?

If so, what is the remedy?

Ed Wright

iTrader: (1)

1) Buy the part of the cable that plugs into the car for a '95 car. Same connector as OBD2.
2) Use a '95 calibration for the TCC. Just copy over all the changes in your '94 calibration .
3)Turn off DTC 43, knock sensor will function perfectly.

ADM

1. I believe this is the cable that you meant? http://www.aldlcable.com/sc/details.asp?item=aldlobd2u

2. How do I get a '95 calibration?

3. This is to be disabled after the knock sensor is changed to OBD I ?

phonedawgz

OBD1 on the vehicle's 16 pin connector requires the data to be on pin 9. You will find the OBD2 data to be on pin 2. You can disassemble the connector and just move the terminal from position 2 to position 9.

The grounds stay on the same pins for both OBD1 and OBD2.

Paul Bell

iTrader: (9)

I'm not sure if this is gonna work. There are transmission differences between OBDI and OBDII.

Ed Wright

iTrader: (1)

1) '94 does not have the pulse width modulated TCC solenoid. 1995 & later does. It's not an OBD1-OBD2 situation.

2) Somebody can email you a 1995 calibration ("tune") I can send you one if you just email me and tell me if you need a 2.73 or 3.23 cal. Just email me and I will attach to the reply.

3) Turn DTC 43 off, you don't need to change the knock sensor. Only done that a couple hundred times. Actually, if you turn the PWM TCC DTC that will work too. I prefer to change cals.

Ed