LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Volkswagen >> 1992 >> Fox Base, 1.8 B >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Engine Sensors & Switches >> Oxygen Sensor
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Oxygen Sensor

  1. Ensure exhaust system is not leaking. Warm engine to normal operating temperature with all accessories off. Remove differential pressure regulator connector. Connect Wiring Harness Adapter (VW 1315 A/1) in series. See Fig 1 .
  2. Attach Multimeter (US 1119) to adapter and set meter on DCA 200m scale. Remove PCV hose and vent to atmosphere. Remove 90 degree "T" connector and insert port with small vent hole into intake air boot. See Fig 2 .
  3. Start engine and allow to run for 2 minutes. Meter reading should start fluctuating. If reading does not fluctuate, raise engine speed to 3000 RPM. If meter reading fluctuates, oxygen sensor is okay. If reading still does not fluctuate, check control unit and wiring harness for short or open circuit.
Fig 1: Testing Oxygen (O2) Sensor
G93045Courtesy of VOLKSWAGEN UNITED STATES, INC.
Fig 2: Positioning Canister Hose For O2 Sensor Test
G121510Courtesy of VOLKSWAGEN UNITED STATES, INC.