what is wrong when there is high CO2 level in a 2005 Chevy Cobalt?
When the car goes above 20 miles an hour my check engine light flashes. I had it checked at Auto Zone and the code gave a high CO2 level reading.
Can you post the 4 digit code?
Possible causes are 1) Faulty HO2S (Lambda) sensor or 2) Faulty coolant temp sensor.
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