Join Date: Oct 2011
Location: Magnetic Hill, New-Brunswick
It's there to measure catalytic efficiency yes, but is also used to trim fuel mixture. If you find your Cobalt to be a bit harder on fuel you will know why. If it's only the heater part that burnt, the HOČ will still work but vehicle will take longer to go into closed loop.
In your case engine will never go into closed loop because it is the sensor itself that is faulty.
P2270: HO2S Signal Stuck Lean Sensor 2
Never drive faster than your guardian angel can fly
Last edited by Coby7; 09-24-2016 at 06:29 AM.