1992 2.3 OBD1 fault 126

It's actually looking at the Barometric pressure sensor. It's basically a MAP used to reference atmospheric pressure rather than manifold pressure.

On the firewall behind the engine just about dead center you'll see a small black module on a bracket. At the bottom it'll have an electrical plug and a small stem. The stem is a cover over the nipple where a vacuum hose would connect if it were a MAP sensor. That's your Baro (or BAP)