Some vehicles can keep as many as four O2 sensors, and they should all be tested.
The O2 sensor on your vehicle has one substantial on the contrary exigent advantage: it tells your vehicle's pc whether the fuel delivery to the engine reads very slim or also plush. The Oxygen sensor usually works when the engine heats up, and in that the sensor works in a closed loop instance passion many other sensors on the vehicle, it can detector the engine's emission management, fuel economy and overall potential. Blameless owing to an engine burnished comes on with an emission control warning does not greedy the Oxygen sensor has failed, on the contrary that a overhaul reminder space has expired, requiring your concern. You can trial the action of the Oxygen sensor in a uncommon light steps and with a scarce tools.
Instructions
1. Allot the transmission shifter in grassland whether you enjoy an automatic; allot the shift in impartial for a book transmission. Allot the emergency brake. Stand the vehivle with a floor jack and corner two jack stands under the front frame and two stands under the rear frame. Slide under the vehicle and allot the Oxygen sensor on the leading exhaust conduit or exhaust manifold, even-handed before the catalytic converter. You might acquire enhanced than one sensor; evaluation your vehicle's owner's tome for the locations.
2. Remove the Oxygen sensor wire connector from the unit; it Testament be toward the engine side. Spray penetrating oil on the Oxygen sensor where it screws into the main or manifold. Let it soak. Field an Oxygen sensor socket over the unit and unscrew it with a ratchet wrench. Be careful not to coercion it; nudge it tight and back it off many times before loosening it.
3. See the tip of the sensor. It should appear smooth and light gray in color. Any white, fluffy scale will indicate water contamination. Any heavy, black soot or carbon will not allow the tip probe to read a signal correctly. Any red discoloration or glue-like substance indicates silicone adhesive has covered the tip, which might have been used on a pan or valve cover gasket.
4. A reading that exceeds 12 ohms or reads to infinity means that the sensor has failed.6. Place the O2 sensor in a bench vice with the probe (not wire) end sticking out. Connect the multimeter leads to the other two colored wires in the connector; they might be blue and white or some other color. Wipe dry with a rag.
5. Set a multimeter to the low reading ohms scale. Connect one lead of the multimeter to one black wire coming out of the sensor and the other multimeter lead to the other black wire, which consists of the heating element wires. Do not allow the meter leads to touch any other pin in the connector. Your reading should display about 12 ohms of resistance. Examine the orifice holes in the body of the O2 sensor up toward the wire connector end and at the probe end. There should be three clean, open holes at both locations. If plugged, use a paper clip to probe the holes open. Clean the O2 sensor with carburetor cleaner and a tooth brush, but do so gently until all scale, mud and debris have been removed.
Turn the multimeter on the low, 2-volt scale. Use the propane torch to heat up the sensor probe until it glows pink.
7. Watch the volt scale when applying heat. It should read 1 volt. Pull the torch away and let the senor cool. The reading should drop to 0 (zero) volts. Perform the heating and cooling several times and watch for the 1 volt drop to 0 (zero). Any other reading will indicate a defective O2 sensor. Check and clean all O2 sensors on your vehicle in the same manner.
