I've searched all over the forum/web and cannot find a decent explanation of what needs to be done.

I'm not a stranger to the OBDI portion of it, did the swap in my S-10, know the wiring diagram about by heart, but what is involved with taking a OBDII to OBDI?

I've seen a post that said you change the knock sensor and plug in the obdi ecm?? is that it? what about the spare o2s? tranny wiring? ALDL?? Please, I need some info guys/gals.

Even if someone could send me a 96/97 ecm wiring diagram/pcm pinout, I would be grateful. I have a friend putting a 97 ss lt1 into a 197* el camino and wants to go obdI to simplify the install and get me to help w/ the tuning/programming.

thanks in advance.

Jeff

 

I did the swap in my '97. The only thing you'll need to do is correct the resistance to the knock sensor. I got my OBD1 PCM from PCM for Less, and he put the resistor inside the PCM housing so that it's a easy to swap the two different PCMs back and forth.

When you put an OBD1 in an OBD2 car, it will ignore the post-cat O2's and the crank position sensor.

 

I'm considering this as well. Mainly because I'm going to '94-'95 single cat headers.

How important is the crank position sensor and what are it's benefits?

Dan

 

crank sensor is on the 96+ obd2 cars, it's in the 7 o'clock position behind your balancer. it reads the crank revs and relays that info to the ecm, like a abs/speed sensor. If the engine experiences a misfire, it can tell the crank lost momentum, and it can tell what cyl didn't fire, thereby helping you determine which cylinder is misfiring. I think they stepped away from using the low res/high res signals from the opti and replaced it w/ the crank sensor. I know on non lt1 motors if the crank sensor isn't working right, the motor won't run.