OK, not to step on anyone's toes, OBD-1 is not a dumb system, it is just the first. Just like we have MS windows now, back in the eighties we used DOS. I have two trucks a 1990 Silverado 1500 and a 1988 K5 Blazer. Both have OBD-1. So, when you start the truck does the "Service Engine Soon"...