Code 21 - Probable Bad Oxygen Sensor
jbreyes
02-24-2004, 01:40 AM
My 1997 Dodge Grand Caravan 2.4L with a 21,000 mileage just had the Service Engine Soon light on. When i checked out what error code it has, it showed the Code 12 and 21 errors.
I looked for it under allpar.com and it says that CODE 12 means battery or computer recently disconnected(not really a problem) while CODE 21 means Oxygen Sensor signal doesn't change. Probably bad oxygen sensor.
I don't experience any problems at this point. Is it that accurate or I can also try and reset the computer by pulling off the negative ground on the battery for about 15 seconds?
If I need to replace the oxygen sensors, do I replace both? What will happen if I delay the replacement?
What symptoms will I see if I have this problem? I have seen some comments like increase in fuel consumption. What causes this type of problem, fuel used? As I have said, I am not exprienceing any problems with my engine at this time.
I looked for it under allpar.com and it says that CODE 12 means battery or computer recently disconnected(not really a problem) while CODE 21 means Oxygen Sensor signal doesn't change. Probably bad oxygen sensor.
I don't experience any problems at this point. Is it that accurate or I can also try and reset the computer by pulling off the negative ground on the battery for about 15 seconds?
If I need to replace the oxygen sensors, do I replace both? What will happen if I delay the replacement?
What symptoms will I see if I have this problem? I have seen some comments like increase in fuel consumption. What causes this type of problem, fuel used? As I have said, I am not exprienceing any problems with my engine at this time.
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