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Why Does a Faulty O2 Sensor Turn On the Check Engine Light?

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Generally, when the oxygen sensor goes bad, it sends its own error code to your automobile’s main computer chip. This chip is called the engine control unit or ECU. Padron Automotive advises when the ECU receives the error code, it will attempt to correct the problem. Because it cannot replace the oxygen sensor itself, it will turn on the check engine light. This is just one sign that your O2 sensor is bad. We are going to list the other signs of a malfunctioning O2 sensor below.

Iffy Engine Performance

Your engine performance is going to be affected by the O2 sensor. This sensor detects how much air is in your vehicle’s exhaust. If it cannot report the correct air volume to the ECU, the ECU may make unnecessary adjustments to the air level in the combustion chamber. If it adds too much air, your engine will sputter. If it adds too little air, the engine will pick up speed unexpectedly.

Poor Fuel Economy

Either problem is going to cause a reduction in the fuel economy that your car, truck, or utility vehicle gets. If the engine is burning away excess fuel, you’re going to head to the service station more often. If the engine is struggling to produce power because there’s too much air in the chamber, it will burn through what little fuel it has quicker than normal.

Catalytic Converter Issues

Let’s assume for the moment that the ECU has reduced the air in the combustion chamber and increased the fuel mistakenly because of the faulty oxygen sensor. This will send excess hydrocarbons into the catalytic converter for it to treat. When this happens, deposits clog the converter and cause it to malfunction prematurely. You may smell rotten eggs in your exhaust as a result.

Black Exhaust Smoke

You may also end up with black exhaust smoke flowing out of the tailpipe. This is a sign that the engine is burning excess fuel. Unfortunately, the ECU is doing what it thinks needs to be done based on the incorrect data from the O2 sensor.

High Emissions Levels

Finally, you will also end up with high emissions levels in your vehicle’s exhaust. This can be very problematic if you need your automobile to pass an emissions test. The automobile is going to fail because of the excess hydrocarbons, the faulty catalytic converter, and the check engine warning.

Call Padron Automotive in Topeka, KS, today if your automobile is having any of the problems listed above or if the check engine light has come on.

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