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CO2 Sensors

Does running gas with high ethanol distroy the CO2 Sensors?

There are CO detectors in your house for carbon monoxide but O2 or oxygen sensors in your car. If a car is built for multi fuels such as ethanol, it should have no impact on the sensors. All they do is measure the level of oxygen in the exhaust and send that information back to the computer to reset the fuel ratio.

Your owner’s manual should tell you what level of ethanol you may use in your car.

No. But running too high of a concentration of ethanol in the gas can mess up the O2 sensor signals.

Ethanol alcohol is oxgenated which means it contains oxygen. If the ethanol concentration is high enough, the O2 sensor detects this higher oxygen in the exhaust gas and the computer will try to adjust the fuel mixture to compensate for this. If the O2 sensor voltage drops too low because of this additional oxygen, the computer will go into a default mode to keep the engine operating and turn on the Check Engine light. But if you go back to no or E10 gasoline, eventually the Check Engine light will turn off and engine will run normally.

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