Gauge Test - Oil Pressure Gauge/Oil Pressure Switch

WARNING: This page is about a different car, the 2002 Ford Ranger. However, it is still accessible from the selected car via links, so may be relevant.

With the Instrument Gauge System Tester attached to the oil pressure switch connector, and the ignition switch lock cylinder in the RUN position (engine not running), set the Instrument Gauge System Tester to infinite resistance. The center line of the pointer should fall on or below the "L" mark.

Short the connector directly to engine ground. The centerline of the pointer should fall slightly above mid-scale.

If the oil pressure gauge tests within calibration, install a new oil pressure switch.
If the oil pressure gauge still tests out of calibration, install a new gauge.