GMC released the Yukon in the 1992 model year as the replacement for the full-sized Jimmy. The 2003 Yukon came standard with a 4.8-liter V-8 engine that produced 275 horsepower and had an optional 285-horsepower 5.3-liter V-8 available. The oil system in these engines requires 6 to 24 psi of oil pressure, depending on the engine's rpm. The oil pressure sensor reads the pressure and alerts the driver if the pressure becomes too low or too high. Replacing a faulty oil pressure sensor on the 2003 Yukon is fairly easy.
Remove the bolt at the front-center of the plastic engine cover, using a ratchet and socket. Pull the front of the cover upward, then pull the entire cover forward to remove it from its retainer. Pull the cover from the engine compartment.
Remove the two bolts securing the engine cover retainer to the engine, using a ratchet and socket, and pull the retainer from the engine.
Locate the oil pressure sensor on the rear of the engine, directly behind the intake manifold. Unplug the oil pressure sensor wiring harness by pressing the locking button and pulling the harness from the sensor.
Remove the oil pressure sensor, using a ratchet and a GM pressure sensor socket (part No. J-41712).
Apply a thin coat of Teflon thread sealer on the threads of the new oil pressure sensor. Install the new oil pressure sensor and torque it to 26 foot-pounds with a torque wrench and GM pressure sensor socket (part No. J-41712).
Plug the wiring harness into the top of the new sensor.
Reinstall the engine cover retainer and tighten the bolts to 3 to 4 foot-pounds with a torque wrench and socket. Place the rear of the engine cover into the engine cover retainer and lower the engine cover onto the top of the engine. Tighten the engine cover bolt to 7 to 8 foot-pounds with a torque wrench and socket.
