Thanks for the reply. I had already thought of that so I plugged it into my 97 454 suburban. It is reporting 25 degress advance. Knock retard = 0.00.
The Pontiac is also reporting 0.00 knock retard. I would think the scanner would report the same -/+ settings for GM 97 OBD11, no matter what engine.
Does this thing have a cam postion sensor or just a crank sensor? I think I will throw a new sensor at it if it's not hard to do.
Test drove the car with the check engine light on. The dealer cleared the codes and repaired the drivers side window and horn before we bought it. Horn doesn't work again.

So, I don't know what the codes that were set before then.
Thanks for the help,
Gayle