Are you getting a "front" (Bank 1) or "rear" (Bank 2) indication? Are the sensors the origionals? If so, on a 96 they're suspect. You can look over in the 700/900 FAQ section for info on trouble shooting them. If you have a digital VOM, set it to the min. voltage setting ( 1v or sometimes 3v) Unplug the 02 sensor connectors (bay 13 has photos) as they're a pain to reach. Each has four wires (black, gray and two white) with the black wire being the "hot" or signal wire. Hook your + VOM lead to the black wire pin and the - lead to ground (hook to the wire coming FROM the sensor). Start the engine and watch the reading. A good front sensor will show a voltage of about .25-.75v and the reading will fluxiate constantly and rapidly. If it doesn't it's probably bad. The rear sensor will read about .25v or so and be fairly constant.

bl